ci: Restore ToC check for ADRs/RFCs (#9180)

* Import presubmit TOC check script from master and fix warning

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Fix misspelled ADR link discovered by presubmit script

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Restore docs-toc workflow

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Create makefile target for docs ToC check

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Use makefile target in CI workflow for docs ToC check

Signed-off-by: Thane Thomson <connect@thanethomson.com>

.github/workflows/docs-toc.yml

@@ -1,21 +1,20 @@
-# TODO(thane): Re-enable once we've pulled in the ADRs and RFCs from master.
 # Verify that important design docs have ToC entries.
-#name: Check documentation ToC
-#on:
-#  pull_request:
-#    push:
-#      branches:
-#        - main
-#
-#jobs:
-#  check:
-#    runs-on: ubuntu-latest
-#    steps:
-#      - uses: actions/checkout@v3
-#      - uses: technote-space/get-diff-action@v6
-#        with:
-#          PATTERNS: |
-#            docs/architecture/**
-#            docs/rfc/**
-#      - run: ./docs/presubmit.sh
-#        if: env.GIT_DIFF
+name: Check documentation ToC
+on:
+  pull_request:
+    push:
+      branches:
+        - main
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            docs/architecture/**
+            docs/rfc/**
+      - run: make check-docs-toc
+        if: env.GIT_DIFF