CI: Support cancelling, update actions & prevent draft releases

Allow the workflow to be cancelled without running all remaining jobs.
On invocation of the workflow, cancel concurrent runs of older commits
automatically.

Replace unmaintained release action with recommended alternative.

After much testing, I found that the problem of releases
being created as draft releases can be traced to a
consistency issue/race condition on GitHub's side.
Prevent this by inserting a generous delay between deleting and
re-creating the edge release.

.github/workflows/cd.yml

@@ -9,9 +9,20 @@ on:
       - created
 
 jobs:
+  cancel_previous_runs:
+    runs-on: ubuntu-latest
+    name: Cancel Previous Runs
+    if: github.event_name == 'push'
+    steps:
+    - uses: styfle/cancel-workflow-action@0.8.0
+      with:
+        access_token: ${{ github.token }}
+
   test_ubuntu:
+    needs: [cancel_previous_runs]
     runs-on: ubuntu-18.04
     name: Test Ubuntu
+    if: "!cancelled()"
     steps:
     - uses: actions/checkout@v2
     - name: Install Dependencies
@@ -20,8 +31,10 @@ jobs:
       run: .github/scripts/build-ubuntu.sh
 
   test_windows:
+    needs: [cancel_previous_runs]
     runs-on: windows-2019
     name: Test Windows
+    if: "!cancelled()"
     steps:
     - uses: actions/checkout@v2
     - name: Install Dependencies
@@ -32,8 +45,10 @@ jobs:
       shell: bash
 
   test_macos:
+    needs: [cancel_previous_runs]
     runs-on: macos-10.15
     name: Test macOS
+    if: "!cancelled()"
     steps:
     - uses: actions/checkout@v2
     - name: Install Dependencies
@@ -164,26 +179,29 @@ jobs:
   update_edge_release:
     name: Update Edge Release
     needs: [build_release_windows, build_release_windows_openmp, build_release_macos]
-    if: always() && github.event_name == 'push'
+    if: github.event_name == 'push' && !cancelled()
     runs-on: ubuntu-latest
     outputs:
       upload_url: ${{ steps.create_release.outputs.upload_url }}
     steps:
     - name: Delete Old Edge Release
-      uses: dev-drprasad/delete-tag-and-release@v0.1.2
+      uses: dev-drprasad/delete-tag-and-release@v0.2.0
       with:
         delete_release: true
         tag_name: edge
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Wait
+      shell: bash
+      run: sleep 60
     - name: Create New Edge Release
       id: create_release
-      uses: actions/create-release@v1
+      uses: softprops/action-gh-release@35d938cf01f60fbe522917c81be1e892074f6ad6
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       with:
         tag_name: edge
-        release_name: Edge
+        name: Edge
         prerelease: true
         draft: false
         body: ${{ github.event.head_commit.message }}
@@ -191,7 +209,7 @@ jobs:
   upload_release_assets:
     name: Upload Release Assets
     needs: [build_release_windows, build_release_windows_openmp, build_release_macos, update_edge_release]
-    if: always()
+    if: "!cancelled()"
     runs-on: ubuntu-latest
     steps:
     - name: Download All Workflow Artifacts