scripted-diff: replace remaining Python test equality asserts

Some Python functional tests still use plain `assert x == y`.
The earlier commits convert the ambiguous assert patterns by hand, so this commit can rewrite the remaining safe cases mechanically.
The verify script excludes `wallet_bumpfee.py`, `test_framework/netutil.py`, and `test_framework/authproxy.py`, which still contain assert forms that the plain line-based substitution would misidentify.

-BEGIN VERIFY SCRIPT-
perl -pi -e 's/^(\s*)assert (.+?) == ([^,#]+?)$/\1assert_equal(\2, \3)/' $(git ls-files -- 'test/functional' \
':(exclude)test/functional/wallet_bumpfee.py' ':(exclude)test/functional/test_framework/netutil.py' ':(exclude)test/functional/test_framework/authproxy.py')
-END VERIFY SCRIPT-

test/functional/wallet_miniscript.py

@@ -301,7 +301,7 @@ class WalletMiniscriptTest(BitcoinTestFramework):
         res = self.ms_sig_wallet.walletprocesspsbt(psbt=psbt, finalize=False)
         psbtin = self.nodes[0].decodepsbt(res["psbt"])["inputs"][0]
         sigs_field_name = "taproot_script_path_sigs" if is_taproot else "partial_signatures"
-        assert len(psbtin[sigs_field_name]) == sigs_count
+        assert_equal(len(psbtin[sigs_field_name]), sigs_count)
         res = self.ms_sig_wallet.finalizepsbt(res["psbt"])
         assert_equal(res["complete"], stack_size is not None)