update yaml

.vsts-ci.yml

@@ -12,6 +12,7 @@ variables:
 # Branches that trigger a build on commit
 trigger:
 - main
+- dev17.0
 
 stages:
 - stage: build

.vsts-pr.yaml

@@ -1,3 +1,13 @@
+# Branches that trigger a build on commit
+trigger:
+- main
+- dev17.0
+
+# Branches that trigger builds on PR
+pr:
+- main
+- dev17.0
+
 variables:
   - name: DOTNET_ROOT
     value: $(Build.SourcesDirectory)\.dotnet