Swift: add swiftmodule hash map testing to frontend_invocations

swift/integration-tests/posix-only/frontend-invocations/.gitignore

@@ -0,0 +1,2 @@
+hashes.expected
+hashes.actual

swift/integration-tests/posix-only/frontend-invocations/test.py

@@ -1,5 +1,21 @@
 from create_database_utils import *
+from subprocess import check_call
+from hashlib import sha256
+from pathlib import Path
 
 run_codeql_database_create([
     './build.sh',
 ], lang='swift')
+
+with open('hashes.expected', 'w') as expected:
+    for f in sorted(Path().glob("*.swiftmodule")):
+        with open(f, 'rb') as module:
+            print(f.name, sha256(module.read()).hexdigest(), file=expected)
+
+with open('hashes.actual', 'w') as actual:
+    hashes = [(s.resolve().name, s.name) for s in Path("db/working/swift-extraction-artifacts/hashes").iterdir()]
+    hashes.sort()
+    for module, hash in hashes:
+        print(module, hash, file=actual)
+
+check_call(['diff', '-u', 'hashes.expected', 'hashes.actual'])