(docs): docs deployment for release branches (#22399)

Note: requires changes from following PR
#22252

Updated build-docs to trigger on release branches. 
Now includes a stage before deployment to check if triggering branch
version matches a latest minor version of a major release.

build-tools/packages/build-cli/src/commands/check/latestVersions.ts

@@ -62,21 +62,23 @@ export default class LatestVersionsCommand extends BaseCommand<typeof LatestVers
 					this.log(
 						`Version ${versionInput.version} is the latest version for major version ${majorVersion}`,
 					);
+					this.log(`##vso[task.setvariable variable=shouldDeploy;isOutput=true]true`);
 					return;
 				}
 
 				// If versions do not match on first major version encounter, then the input version is not the latest
-				this.error(
-					`skipping deployment stage. input version ${versionInput.version} does not match the latest version ${v.version}`,
-					{ exit: 1 },
+				this.log(
+					`##[warning]skipping deployment stage. input version ${versionInput.version} does not match the latest version ${v.version}`,
 				);
+				this.log(`##vso[task.setvariable variable=shouldDeploy;isOutput=true]false`);
+				return;
 			}
 		}
 
 		// Error if no major version corresponds to input version
-		this.error(
-			`No major version found corresponding to input version ${versionInput.version}`,
-			{ exit: 1 },
+		this.log(
+			`##[warning]No major version found corresponding to input version ${versionInput.version}`,
 		);
+		this.log(`##vso[task.setvariable variable=shouldDeploy;isOutput=true]false`);
 	}
 }

tools/pipelines/build-docs.yml

@@ -95,7 +95,7 @@ variables:
 trigger:
   branches:
     include:
-    # - release/*
+    - release/*
     - main
 pr: none
 
@@ -301,10 +301,43 @@ stages:
             workingDir: $(Build.SourcesDirectory)/docs
             customCommand: 'run ci:linkcheck'
 
+- stage: check_branch_version
+  displayName: 'Check Version Deployment Condition'
+  pool: Small
+  jobs:
+    - job: check_branch_version
+      displayName: 'Check Version Deployment Condition'
+      steps:
+        - template: /tools/pipelines/templates/include-install-build-tools.yml
+          parameters:
+            buildDirectory: $(Build.SourcesDirectory)
+        - task: Bash@3
+          name: SetVersion
+          displayName: 'Set Build Version'
+          env:
+            VERSION_BUILDNUMBER: $(Build.BuildNumber)
+          inputs:
+            targetType: 'inline'
+            workingDirectory: $(Build.SourcesDirectory)
+            script: |
+              # Generate the build version. Sets the environment variables version, codeVersion, and isLatest.
+              flub generate buildVersion
+        - task: Bash@3
+          name: SetShouldDeploy
+          displayName: 'Check Version Deployment Condition'
+          inputs:
+            targetType: 'inline'
+            workingDirectory: $(Build.SourcesDirectory)
+            script: |
+              # Check if the version is the latest minor of its corresponding major version series
+              # Sets variable shouldDeploy to true if the version is the latest minor and false otherwise
+              flub check latestVersions $(SetVersion.version) client
+
 - stage: deploy
   displayName: 'Deploy website'
   pool: Small
-  dependsOn: ['build', 'guardian']
+  dependsOn: ['build', 'guardian', 'check_branch_version']
+  condition: eq(dependencies.check_branch_version.outputs['check_branch_version.SetShouldDeploy.shouldDeploy'], 'true')
   jobs:
     - job: deploy_site
       displayName: 'Deploy website'