fix: tolerate unavailable unsigned signature inspection

SOURCE_MANIFEST.txt

@@ -119,7 +119,7 @@ b83d443f5724ac15393567f3a688aed8315fbe3e5966832c864a9466e0669464          8102
 444b397d515d65a7ee59d3088cba869cbb812d2b8cc18fc5d255105e3edb58c2          1468  scripts/serve-demo.mjs
 c76507857292c5713e1c699cf02e24b80265da39af2cecd148034bdb874adbb6          5246  scripts/test-authenticode-chain.ps1
 4393f7dc5f417e6d601a68238f4e26791799a3634acec228fe4d79deaee85eb5          3109  scripts/validate-installed-connections.cjs
-50880ac76b7d681dc65019dc794efc3cea4ffd379507fe0518985312f5b39304          2096  scripts/verify-release-signatures.mjs
+e6127e1e62f39c70ddb1abf72f4d7e7b8e3f19ff1f219e1a3660353c2e0cdfac          2411  scripts/verify-release-signatures.mjs
 c1763bad24b747051ad18d911ba9c7176882663e3b6ce9921a2f8b1aae056bd7         18156  scripts/verify.mjs
 0b9f03ba3c67ff7cdb2916a902ad8ce25e81a7c90b210e4ae52d2ad029efabf3          2353  scripts/write-release-checksums.mjs
 619515f524cb89960370ffcbd3fafd3c0e178b95f69c5868b1dd44777f23ec1e          2081  setup-windows.ps1
@@ -224,7 +224,7 @@ e631e9ca49a5bac7075860aac2ff4d377a32a78377b70e06ecf833f0f192fd5f         11552
 0d1bc4d623ce299337736c577ec61c8ffd6974ebe20335b72838d10eae35ecb1          7993  tests/ssh-service.test.mjs
 8a6a8477eb94b85ccef18cddd2640afb0d1eafa679c96bc7de20428d5d69e1be          1794  tests/tool-invocation.test.mjs
 4182b61e395aff310b9a964c973a43c3566df0b44c454054c3abdd9459e86e3b         49134  tests/unraid-deployment.test.mjs
-c93d9706eb206b17db8ba490a1e93067f654c66595325f34532d0b1d7617fedc         19691  tests/update-service.test.mjs
+edec1007826bff6b5457fca603d8c816a9e1eedb3ce398269f151144ae3d2197         19764  tests/update-service.test.mjs
 9cea5c1d5ba3e0972a0b5c7236cf1f7c5616373e0a39ea4a492ecebf70452e40           948  tests/validation.test.mjs
 7ef4d4b9f5f3e6979293b29d571ce0e39f83197f3cade2d999a9cea7bacdd84d          1781  tests/zip-writer.test.mjs
 8f36b542736f2933bad8b9464ad7fa37b68196009c81cf702ce3b677cd637dea           767  UPDATE_FROM_0.3.2.md