Clear workspace pull state on document close to prevent stale diagnostics (#1674)

* Clear workspace pull state on document close to prevent stale diagnostics

* Update client/src/common/diagnostic.ts

Co-authored-by: Joey Robichaud <joseph.robichaud@microsoft.com>

---------

Co-authored-by: Joey Robichaud <joseph.robichaud@microsoft.com>

Author: dibarbet

client/src/common/diagnostic.ts

@@ -416,6 +416,11 @@ class DiagnosticRequestor implements Disposable {
 					this.forget(PullState.document, document);
 				});
 			}
+
+			// The previous resultId from the workspace pull state can map to diagnostics we no longer have
+			// (e.g. they came from a workspace report but were overwritten by a later document pull request).
+			// Clear the workspace pull state for this document as well to ensure we get fresh diagnostics.
+			this.forget(PullState.workspace, document);
 		} else {
 			// We have normal pull or inter file dependencies. In this case we
 			// clear the diagnostics (to have the same start as after startup).