Fetch correct default branch in toolbar (#24)

Signed-off-by: Mahendra Paipuri <[email protected]>

Author: mahendrapaipuri

src/browser.ts

@@ -55,7 +55,7 @@ export class GitLabFileBrowser extends Widget {
             url,
             resource.repository,
             'tree',
-            'master',
+            this._drive.defaultBranch,
             resource.path
           );
         }

src/contents.ts

@@ -156,6 +156,13 @@ export class GitLabDrive implements Contents.IDrive {
     this._accessToken = token;
   }
 
+  /**
+   * The repository default branch
+   */
+  get defaultBranch(): string {
+    return this._defaultBranch || 'main';
+  }
+
   /**
    * Get a file or directory.
    *