Update CI build to run on v1.x branch

Author: jcouball

.github/workflows/continuous-integration.yml

@@ -4,10 +4,10 @@ name: Continuous Integration
 
 on:
   push:
-    branches: [main]
+    branches: [main, v1.x]
 
   pull_request:
-    branches: [main]
+    branches: [main, v1.x]
 
 jobs:
   build:

.github/workflows/semver_pr_label.yml

@@ -2,7 +2,7 @@ name: Semver PR Label
 
 on:
   pull_request:
-    branches: [main]
+    branches: [main, v1.x]
 
     # The default triggers for pull requests are opened, synchronize, and reopened.
     # Add labeled and unlabeled to the list of triggers so that the