Fixup PR workflow

Make the name more indicative of the work being performed and ensure we
are only running the job on pushes to the master branch.

Signed-off-by: Joshua Lock <[email protected]>

Author: joshuagl

.github/workflows/pr.yml

@@ -1,10 +1,12 @@
 name: CI
 on:
-  pull_request: {}
+  pull_request:
+    branches:
+      - master
 
 jobs:
   main:
-    name: Build, Validate and Deploy
+    name: Check date and version are updated
     runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v2