Fix key warning

Summary: Crash reporter generated React errors because the different lines in a stack trace are not per definition unique

Reviewed By: jknoxville

Differential Revision: D26201941

fbshipit-source-id: 084e0157b1fa3b8216d35f62f0dc17b0d6414b8e

desktop/plugins/crash_reporter/index.tsx

@@ -782,12 +782,9 @@ export default class CrashReporterPlugin extends FlipperDevicePlugin<
                 },
               ]}>
               <Line />
-              {children.map((child) => {
+              {children.map((child, index) => {
                 return (
-                  <StackTraceComponent
-                    key={child.message}
-                    stacktrace={child.message}
-                  />
+                  <StackTraceComponent key={index} stacktrace={child.message} />
                 );
               })}
             </ContextMenu>