src/testUtils: hide running test StatusBarItem after cancelling tests

TESTED=manually

Change-Id: I0472e10c5814f420c22bbc453897291c02776bd0
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/268838
Trust: Hyang-Ah Hana Kim <hyangah@gmail.com>
Trust: Peter Weinberger <pjw@google.com>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Peter Weinberger <pjw@google.com>
diff --git a/src/testUtils.ts b/src/testUtils.ts
index ceb05af..35a66d0 100644
--- a/src/testUtils.ts
+++ b/src/testUtils.ts
@@ -490,6 +490,7 @@
 		});
 		// All processes are now dead. Empty the array to prepare for the next run.
 		runningTestProcesses.splice(0, runningTestProcesses.length);
+		statusBarItem.hide();
 		resolve(true);
 	});
 }