Update GitHub workflows to use checkout v3 (#60)

Author: labkey-tchad

.github/workflows/branch_release.yml

@@ -15,7 +15,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Create branches and PRs
         uses: LabKey/gitHubActions/branch-release@develop

.github/workflows/merge_release.yml

@@ -17,7 +17,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
 
       - name: Merge PR
         uses: LabKey/gitHubActions/merge-release@develop