ci: cancel superseded pull request runs (#2132)

CodeQL has been failing on main since #2105: `init` is on v4.37.9 while
`autobuild` and `analyze` are on v4.37.8, and the action rejects a
config written by a newer version ("Loaded a configuration file for
version '4.37.9', but running version '4.37.8'"). Dependabot bumps the
three steps in separate pull requests, so #2119 and #2120 each still
fail on their own and main has gone red at every partial bump (08-19,
08-28, today).

This moves the two steps to v4.37.9, the same commit dependabot picked
in #2119 and #2120, and groups `github/codeql-action*` in dependabot so
the three bump together from now on. Supersedes #2119 and #2120.

## Launch Checklist

 - [x] Briefly describe the changes in this PR.
- [ ] Add an entry to `CHANGELOG.md` under the `## main` section (not
applicable, CI only).

.github/dependabot.yml

@@ -31,6 +31,10 @@ updates:
     directory: "/"
     schedule:
       interval: "daily"
+    groups:
+      codeql-action:
+        patterns:
+          - "github/codeql-action*"
     cooldown:
       default-days: 3
       # no semver support for github-actions

.github/workflows/ci.yml

@@ -6,6 +6,10 @@ on:
   push:
     branches: [ main ]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
 jobs:
 
   build-node:

.github/workflows/codeql-analysis.yml

@@ -20,6 +20,10 @@ on:
   schedule:
     - cron: '17 0 * * 6'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
 jobs:
   analyze:
     name: Analyze
@@ -53,7 +57,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@db488ddef3bf6cb639b32c2e9a7c0a7ea8271d28 # v4.37.8
+      uses: github/codeql-action/autobuild@cdf488f595d80d6e07e03d4674febd5ab45fa938 # v4.37.9
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 https://git.io/JvXDl
@@ -67,4 +71,4 @@ jobs:
     #   make release
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@db488ddef3bf6cb639b32c2e9a7c0a7ea8271d28 # v4.37.8
+      uses: github/codeql-action/analyze@cdf488f595d80d6e07e03d4674febd5ab45fa938 # v4.37.9