git_panel: Improve toast messages for push/pull/fetch (#35092)

On GitLab, when pushing a branch and a MR already existing the remote
log contains "View merge request" and the link to the MR.

Fixed `Already up to date` stdout check on pull (was `Everything up to
date` on stderr)
Fixed `Everything up-to-date` check on push (was `Everything up to
date`)
Improved messaging for up-to-date for fetch/push/pull
Fixed tests introduced in
https://github.com/zed-industries/zed/pull/33833.

<img width="470" height="111" alt="Screenshot 2025-07-31 at 18 37 05"
src="https://github.com/user-attachments/assets/2a5dcc4c-6f53-4a85-b983-8e25149efcc0"
/>

Release Notes:

- Git UI: Add "View Pull Request" when pushing to Gitlab remotes
- git: Improved toast messages on fetch/push/pull

---------

Co-authored-by: Peter Tripp <peter@zed.dev>

crates/git_ui/Cargo.toml

@@ -70,6 +70,7 @@ windows.workspace = true
 ctor.workspace = true
 editor = { workspace = true, features = ["test-support"] }
 gpui = { workspace = true, features = ["test-support"] }
+indoc.workspace = true
 pretty_assertions.workspace = true
 project = { workspace = true, features = ["test-support"] }
 settings = { workspace = true, features = ["test-support"] }