Add GitLabCredentials placeholder text for token field

CHANGELOG.md

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## Unreleased
 
 ### Added
+- Add placeholder text to `GitLabCredentials` token field in UI - [#23](
+    https://github.com/PrefectHQ/prefect-gitlab/pull/23/)
 
 ### Changed
 

prefect_gitlab/credentials.py

@@ -32,6 +32,7 @@ class GitLabCredentials(Block):
         name="Personal Access Token",
         default=None,
         description="A GitLab Personal Access Token with read_repository scope.",
+        example="oauth2:my-token",
     )
     url: str = Field(
         default=None, title="URL", description="URL to self-hosted GitLab instances."