[runtime] Don't forget to free the method field in MonoMethodSignatures.

[rolfbjarne]

Before:

There were 258096 MonoObjects created, 246948 MonoObjects freed, so 11148 were not freed. (dynamic registrar)
There were 205834 MonoObjects created, 205214 MonoObjects freed, so 620 were not freed. (static registrar)

After:

There were 205834 MonoObjects created, 205222 MonoObjects freed, so 612 were not freed. (dynamic registrar)
There were 258100 MonoObjects created, 258019 MonoObjects freed, so 81 were not freed. (static registrar)

[vs-mobiletools-engineering-service2]

❌ [PR Build] Tests failed on Build ❌

Tests failed on Build.

• Azure DevOps
• Html Report (VSDrops)

API diff

✅ API Diff from stable

View API diff

• iOS vsdrops gist
• macOS vsdrops gist
• macCat vsdrops gist
• macCatiOS gist
• tvOS vsdrops gist
• watchOS vsdrops gist

API & Generator diff

✅ API Diff (from PR only) (no change)
✅ Generator Diff (no change)

GitHub pages

Results can be found in the following github pages (it might take some time to publish):

• Test results
• API diff
• API & Generator diff

Test results

1 tests failed, 107 tests passed.

Failed tests

• monotouch-test/Mac [dotnet]/Debug (CoreCLR) [dotnet]: Failed (Test run failed.
  Tests run: 2444 Passed: 2356 Inconclusive: 7 Failed: 2 Ignored: 86)

Pipeline on Agent XAMBOT-1100.BigSur
Merge 4af29b9 into 8d6893c

[rolfbjarne]

Test failure is unrelated and will be fixed with #11732.