.github/workflows: use ofborg-eval context for pending status

Instead of adding a pending status with context `Wait for ofborg`, make
the context `ofborg-eval` and the description "Wait for OfBorg...". That
way, the status will be reused by OfBorg when it starts evaluation and
we don't need to clear it any more.

.github/workflows/ofborg-pending.yml

@@ -0,0 +1,33 @@
+name: "Set pending OfBorg status"
+on:
+  pull_request_target:
+
+# Sets the ofborg-eval status to "pending" to signal that we are waiting for
+# OfBorg even if it is running late. The status will be overwritten by OfBorg
+# once it starts evaluation.
+
+# WARNING:
+# When extending this action, be aware that $GITHUB_TOKEN allows (restricted) write access to
+# the GitHub repository. This means that it should not evaluate user input in a
+# way that allows code injection.
+
+permissions:
+  contents: read
+
+jobs:
+  action:
+    if: github.repository_owner == 'NixOS'
+    permissions:
+      statuses: write
+    runs-on: ubuntu-latest
+    steps:
+    - name: "Set pending OfBorg status"
+      env:
+        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      run: |
+        curl \
+          -X POST \
+          -H "Accept: application/vnd.github.v3+json" \
+          -H "Authorization: Bearer $GITHUB_TOKEN" \
+          -d '{"context": "ofborg-eval", "state": "pending", "description": "Waiting for OfBorg..."}' \
+          "https://api.github.com/repos/NixOS/nixpkgs/commits/${{ github.event.pull_request.head.sha }}/statuses"

.github/workflows/pending-clear.yml

@@ -1,26 +0,0 @@
-name: "clear pending status"
-
-on:
-  check_suite:
-    types: [ completed ]
-
-permissions:
-  contents: read
-
-jobs:
-  action:
-    permissions:
-      statuses: write
-    runs-on: ubuntu-latest
-    steps:
-    - name: clear pending status
-      if: github.repository_owner == 'NixOS' && github.event.check_suite.app.name == 'OfBorg'
-      env:
-        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      run: |
-        curl \
-          -X POST \
-          -H "Accept: application/vnd.github.v3+json" \
-          -H "Authorization: token $GITHUB_TOKEN" \
-          -d '{"state": "success", "target_url": " ", "description": " ", "context": "Wait for ofborg"}' \
-          "https://api.github.com/repos/NixOS/nixpkgs/statuses/${{ github.event.check_suite.head_sha }}"

.github/workflows/pending-set.yml

@@ -1,30 +0,0 @@
-name: "set pending status"
-
-on:
-  pull_request_target:
-
-# WARNING:
-# When extending this action, be aware that $GITHUB_TOKEN allows write access to
-# the GitHub repository. This means that it should not evaluate user input in a
-# way that allows code injection.
-
-permissions:
-  contents: read
-
-jobs:
-  action:
-    permissions:
-      statuses: write
-    runs-on: ubuntu-latest
-    steps:
-    - name: set pending status
-      if: github.repository_owner == 'NixOS'
-      env:
-        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      run: |
-        curl \
-          -X POST \
-          -H "Accept: application/vnd.github.v3+json" \
-          -H "Authorization: token $GITHUB_TOKEN" \
-          -d '{"state": "pending", "target_url": " ", "description": "This pending status will be cleared when ofborg starts eval.", "context": "Wait for ofborg"}' \
-          "https://api.github.com/repos/NixOS/nixpkgs/statuses/${{ github.event.pull_request.head.sha }}"