[8.14] Sync auto approve actions with main (#187918)

## Summary

Workflows are based on their state in the target branch, so this brings
the two actions in sync with `main` so we can backport in the future if
needed and the behavior is consistent.

[7.17 PR](#187919)

.github/workflows/auto-approve-api-docs.yml

@@ -0,0 +1,18 @@
+on:
+  pull_request_target:
+    branches:
+      - main
+    types:
+      - opened
+
+jobs:
+  approve:
+    name: Auto-approve API docs
+    runs-on: ubuntu-latest
+    if: |
+      startsWith(github.event.pull_request.head.ref, 'api_docs') &&
+      github.event.pull_request.user.login == 'kibanamachine'
+    permissions:
+      pull-requests: write
+    steps:
+      - uses: hmarr/auto-approve-action@f0939ea97e9205ef24d872e76833fa908a770363 #4.0.0

.github/workflows/auto-approve-backports.yml

@@ -2,6 +2,8 @@ on:
   pull_request_target:
     branches-ignore:
       - main
+    types:
+      - opened
 
 jobs:
   approve:
@@ -13,4 +15,4 @@ jobs:
     permissions:
       pull-requests: write
     steps:
-      - uses: hmarr/auto-approve-action@v3
+      - uses: hmarr/auto-approve-action@f0939ea97e9205ef24d872e76833fa908a770363 #4.0.0