ci: bump flamegraph to v1.9.5 and make the step non-blocking

The flamegraph action crashes in its Combine Time Traces step with
write EINVAL on the runner, independent of action version or Node
runtime: its log stream is a socket under docker exec and the writev is
rejected. The flamegraph is a non-critical compile-time diagnostic and
the time-trace matrix variant still validates the -ftime-trace build,
so mark the step continue-on-error rather than gate CI on a broken
upstream post-processing step. Also bump to v1.9.5 (latest) and rename
the github_token input to github-token to clear the deprecated-input
warning.

Author: sgerbino

.github/workflows/ci.yml

@@ -676,12 +676,13 @@ jobs:
                 --warnings-as-errors='*'
 
       - name: FlameGraph
-        uses: alandefreitas/cpp-actions/flamegraph@v1.9.0
+        uses: alandefreitas/cpp-actions/flamegraph@v1.9.5
         if: matrix.time-trace
+        continue-on-error: true
         with:
           source-dir: corosio-root
           build-dir: corosio-root/__build__
-          github_token: ${{ secrets.GITHUB_TOKEN }}
+          github-token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Generate Coverage Report
         if: ${{ matrix.coverage && matrix.linux }}