cmd/testwrapper: temporarily remove test coverage support

testwrapper doesn't work with Go 1.24 and the coverage support is
making it harder to debug.

Updates #15015
Updates tailscale/corp#26659

Change-Id: I0125e881d08c92f1ecef88b57344f6bbb571b569
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

.github/workflows/test.yml

@@ -64,7 +64,6 @@ jobs:
       matrix:
         include:
           - goarch: amd64
-            coverflags: "-coverprofile=/tmp/coverage.out"
           - goarch: amd64
             buildflags: "-race"
             shard: '1/3'
@@ -119,15 +118,10 @@ jobs:
     - name: build test wrapper
       run: ./tool/go build -o /tmp/testwrapper ./cmd/testwrapper
     - name: test all
-      run: NOBASHDEBUG=true PATH=$PWD/tool:$PATH /tmp/testwrapper ${{matrix.coverflags}} ./... ${{matrix.buildflags}}
+      run: NOBASHDEBUG=true PATH=$PWD/tool:$PATH /tmp/testwrapper ./... ${{matrix.buildflags}}
       env:
         GOARCH: ${{ matrix.goarch }}
         TS_TEST_SHARD: ${{ matrix.shard }}
-    - name: Publish to coveralls.io
-      if: matrix.coverflags != '' # only publish results if we've tracked coverage
-      uses: shogo82148/actions-goveralls@v1
-      with:
-        path-to-profile: /tmp/coverage.out
     - name: bench all
       run: ./tool/go test ${{matrix.buildflags}} -bench=. -benchtime=1x -run=^$ $(for x in $(git grep -l "^func Benchmark" | xargs dirname | sort | uniq); do echo "./$x"; done)
       env: