[analysis_server] Update LSP format tests to use EOL normalization

This is work towards making all tests normalize EOLs to the current platform by default.

See #60234

Change-Id: Icbc6055194cd8a5a574138db96703330f5dc1f49
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/455100
Commit-Queue: Brian Wilkerson <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Samuel Rawlins <[email protected]>

Author: DanTup