Shorten timeouts on macOS and MinGW

From recent results, `check` and `test-all` will finish within 10
 minutes on macOS or 30 minutes on MinGW, otherwise time out.

.github/workflows/macos.yml

@@ -39,7 +39,7 @@ jobs:
       - run: make prepare-gems
         if: ${{ matrix.test_task == 'check' }}
       - run: make $JOBS -s ${{ matrix.test_task }}
-        timeout-minutes: 60
+        timeout-minutes: 15
         env:
           RUBY_TESTOPTS: "-q --tty=no"
           TEST_BUNDLED_GEMS_ALLOW_FAILURES: "rexml"

.github/workflows/mingw.yml

@@ -87,7 +87,7 @@ jobs:
           make -j $jobs update-gems
 
       - name: make all
-        timeout-minutes: 40
+        timeout-minutes: 20
         run: |
           $jobs = [int](2 * $env:NUMBER_OF_PROCESSORS)
           make -j $jobs
@@ -108,7 +108,7 @@ jobs:
           make test
 
       - name: test-all
-        timeout-minutes: 60
+        timeout-minutes: 30
         run: |
           # Actions uses UTF8, causes test failures, similar to normal OS setup
           $PSDefaultParameterValues['*:Encoding'] = 'utf8'