Demote handled doctor check failures to warning

Summary:
- It's handled.
- It's already user-visible.
- It's usually timeouts which aren't actionable.

Reviewed By: lblasa

Differential Revision: D48642582

fbshipit-source-id: ccb3e56d4937bec2f9e887b7d62b98806140b2e8

desktop/flipper-ui-core/src/utils/runHealthchecks.tsx

@@ -58,7 +58,7 @@ async function launchHealthchecks(options: HealthcheckOptions): Promise<void> {
           h.key,
         )
         .catch((e) => {
-          console.error('Failed to run doctor check', e);
+          console.warn('Failed to run doctor check', e);
           return {
             status: 'FAILED',
             isAcknowledged: false,