wallet2: fix rescanning tx via scan_tx

- Detach & re-process txs >= lowest scan height
- ensures that if a user calls scan_tx(tx1) after scanning tx2,
the wallet correctly processes tx1 and tx2
- if a user provides a tx with a height higher than the wallet's
last scanned height, the wallet will scan starting from that tx's
height
- scan_tx requires trusted daemon iff need to re-process existing
txs: in addition to querying a daemon for txids, if a user
provides a txid of a tx with height *lower* than any *already*
scanned txs in the wallet, then the wallet will also query the
daemon for all the *higher* txs as well. This is likely
unexpected behavior to a caller, and so to protect a caller from
revealing txid's to an untrusted daemon in an unexpected way,
require the daemon be trusted.

.github/workflows/build.yml

@@ -151,7 +151,7 @@ jobs:
     - name: install monero dependencies
       run: ${{env.APT_INSTALL_LINUX}}
     - name: install Python dependencies
-      run: pip install requests psutil monotonic zmq
+      run: pip install requests psutil monotonic zmq deepdiff
     - name: tests
       env:
         CTEST_OUTPUT_ON_FAILURE: ON