ref(crons): Consistent button sizing on alert (#62040)

<img width="904" alt="image"
src="https://github.com/getsentry/sentry/assets/9372512/593a657c-c25c-458d-95ab-f358d0380838">

Author: David Wang

static/app/views/monitors/components/monitorIssues.tsx

@@ -59,7 +59,7 @@ function MonitorIssues({orgSlug, monitor, monitorEnvs}: Props) {
           trailingItems={
             <ButtonBar gap={1}>
               <LinkButton
-                size="sm"
+                size="xs"
                 to={{
                   pathname: `/organizations/${orgSlug}/crons/${monitor.slug}/edit/`,
                   query: {