[release/7.0-rc2] Fixing SpanHelpers.LastIndexOfAnyValueType to no longer create out of bounds GC refs#75885

carlossanlop merged 3 commits intorelease/7.0-rc2dotnet/runtime:release/7.0-rc2from

backport/pr-75857-to-release/7.0-rc2dotnet/runtime:backport/pr-75857-to-release/7.0-rc2Copy head branch name to clipboard