Add missing provider credentials when updating the bare repo in multi-revision assets

modules/nextflow/src/main/groovy/nextflow/scm/MultiRevisionRepositoryStrategy.groovy

@@ -177,7 +177,11 @@ class MultiRevisionRepositoryStrategy extends AbstractRepositoryStrategy {
         }
         final updateRevision = revision ?: getDefaultBranch(manifest)
         log.debug "Fetching (updating) bare repo for ${project} [revision: $updateRevision]"
-        getBareGit().fetch().setRefSpecs(refSpecForName(updateRevision)).call()
+        final fetch = getBareGit().fetch().setRefSpecs(refSpecForName(updateRevision))
+        if( provider.hasCredentials() ) {
+            fetch.setCredentialsProvider(provider.getGitCredentials())
+        }
+        fetch.call()
     }
 
     private void createBareRepo(Manifest manifest) {

modules/nextflow/src/test/groovy/nextflow/scm/AssetManagerTest.groovy

@@ -186,6 +186,7 @@ class AssetManagerTest extends Specification {
 
     }
 
+    @Requires({System.getenv('NXF_GITHUB_ACCESS_TOKEN')})
     def 'test download from tag twice with multi-revision'() {
 
         given:
@@ -317,6 +318,26 @@ class AssetManagerTest extends Specification {
         noExceptionThrown()
     }
 
+    @Requires({System.getenv('NXF_AZURE_REPOS_TOKEN')})
+    def 'test download from branch twice with multi-revision private repo'() {
+
+        given:
+        def folder = tempDir.getRoot()
+        def token  = System.getenv('NXF_AZURE_REPOS_TOKEN')
+
+        def manager = new AssetManager().build('https://dev.azure.com/pditommaso/nf-azure-repo', [providers: [azurerepos: [ auth: token]]])
+        manager.setStrategyType(AssetManager.RepositoryStrategyType.MULTI_REVISION)
+
+        when:
+        manager.download("master")
+        then:
+        folder.resolve(REPOS_SUBDIR + '/pditommaso/nf-azure-repo/nf-azure-repo/' + BARE_REPO).isDirectory()
+        when:
+        manager.download("master")
+        then:
+        noExceptionThrown()
+    }
+
     // First clone a repo with a tag, then forget to include the -r argument
     // when you execute nextflow.
     // Note that while the download will work, execution will fail subsequently