fix: make CI workflows run after pushing excemptions for cargo-vet

This commits changes the CI for dependabot PRs such that initially, only the exemptions for cargo vet are regenerated and pushed to the PR.
Only after that, all other workflows are triggered. This ensures that the CI result for dependabot PRs is properly presented on github.

.github/workflows/qc.yaml

@@ -3,6 +3,10 @@ on:
   pull_request:
   push:
     branches: [main]
+  workflow_run:
+    workflows: [Regenerate cargo-vet exemptions for dependabot-PRs]
+    types:
+      - completed
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -14,6 +18,8 @@ permissions:
 
 jobs:
   prettier:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4
@@ -22,6 +28,8 @@ jobs:
           args: --check .
 
   shellcheck:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     name: Shellcheck
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
@@ -30,6 +38,8 @@ jobs:
         uses: ludeeus/action-shellcheck@master
 
   rustfmt:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     name: Rust Format
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
@@ -38,6 +48,8 @@ jobs:
         run: bash format_rust_code.sh --mode check
 
   cargo-bench:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4
@@ -56,6 +68,8 @@ jobs:
       - run: RUST_MIN_STACK=8388608 cargo bench --workspace --exclude rosenpass-fuzzing
 
   mandoc:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     name: mandoc
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
@@ -66,6 +80,8 @@ jobs:
         run: doc/check.sh doc/rp.1
 
   cargo-audit:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4
@@ -74,6 +90,8 @@ jobs:
           token: ${{ secrets.GITHUB_TOKEN }}
 
   cargo-clippy:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4
@@ -93,6 +111,8 @@ jobs:
           args: --all-features
 
   cargo-doc:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4
@@ -112,6 +132,8 @@ jobs:
       - run: RUSTDOCFLAGS="-D warnings" cargo doc --no-deps --document-private-items
 
   cargo-test:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
@@ -135,6 +157,8 @@ jobs:
       - run: RUST_MIN_STACK=8388608 cargo test --workspace --all-features
 
   cargo-test-nix-devshell-x86_64-linux:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on:
       - ubicloud-standard-2-ubuntu-2204
     steps:
@@ -158,6 +182,8 @@ jobs:
       - run: nix develop --command cargo test --workspace --all-features
 
   cargo-fuzz:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     env:
     steps:
@@ -192,6 +218,8 @@ jobs:
           cargo fuzz run fuzz_vec_secret_alloc_memfdsec_mallocfb -- -max_total_time=5
 
   codecov:
+    # Only run this for dependabot PRs if it's triggered by the workflow to regenerate cargo-vet exemptions
+    if: ${{ github.actor != 'dependabot[bot]' || github.event_name == 'workflow_run' }}
     runs-on: ubicloud-standard-2-ubuntu-2204
     steps:
       - uses: actions/checkout@v4