style: feedback from code review

Author: mshanemc

src/commands/force/org/display.ts

@@ -103,7 +103,9 @@ export class OrgDisplayCommand extends SfdxCommand {
       };
     }
     throw new SfdxError(
-      `No information for scratch org with ID ${sfdc.trimTo15(orgId)} found in Dev Hub ${hubOrg.getUsername()}`
+      `No information for scratch org with ID ${sfdc.trimTo15(orgId)} found in Dev Hub ${hubOrg.getUsername()}`,
+      'NoScratchInfo',
+      ['Check that the DevHub is accessible and the ScratchOrgInfo record exists and try again']
     );
   }
 }

src/shared/orgListUtil.ts

@@ -127,7 +127,7 @@ export class OrgListUtil {
           // Theory: within <orgId>.json, if the userId is the first entry, that's the primary username.
           if (orgFileNames.includes(orgFileName)) {
             const usernames = ((await fs.readJson(join(Global.DIR, orgFileName))) as { usernames: string[] }).usernames;
-            if (usernames && usernames[0] && usernames[0] === auth.getFields().username) {
+            if (usernames && usernames[0] === auth.getFields().username) {
               return auth;
             }
           }