fix mac coverage collection (#317)

* explicit

* yml

* proj

* ext

Author: bitfaster

.github/workflows/gate.yml

@@ -71,7 +71,7 @@ jobs:
       uses: coverallsapp/github-action@master   
       with:
         github-token: ${{ secrets.GITHUB_TOKEN }} 
-        path-to-lcov: BitFaster.Caching.UnitTests/TestResults/coverage.info
+        path-to-lcov: /Users/runner/work/BitFaster.Caching/BitFaster.Caching/BitFaster.Caching.UnitTests/coverage.info
         flag-name: mac
         parallel: true
     - name: Generate unit test report

BitFaster.Caching.UnitTests/BitFaster.Caching.UnitTests.csproj

@@ -24,4 +24,8 @@
     <ProjectReference Include="..\BitFaster.Caching\BitFaster.Caching.csproj" />
   </ItemGroup>
 
+  <PropertyGroup>
+    <CollectCoverage>true</CollectCoverage>
+    <CoverletOutputFormat>lcov</CoverletOutputFormat>
+  </PropertyGroup>
 </Project>