Should not throw when creating initials on event with undefined username (#33)

* Should not throw when creating initials on event with undefined username
Fixes #32

* Fixes broken test

Author: bobbyg603

src/crash/crash-api-client/crash-api-client.e2e.ts

@@ -28,7 +28,7 @@ describe('CrashApiClient', () => {
     describe('reprocessCrash', () => {
         it('should return 200 for database fred and a recent crash that has symbols', async () => {
             // TODO BG https://github.com/BugSplat-Git/bugsplat-js-api-client/issues/19
-            const response = await client.reprocessCrash(database, 100820);
+            const response = await client.reprocessCrash(database, 103339);
 
             expect(response.success).toEqual(true);
         });

src/events/event/create-event-from-api-response.ts

@@ -21,5 +21,5 @@ function getInitialsOrDefault(event: any): string {
         return `${firstInitial}${lastInitial}`;
     }
 
-    return event.username.substring(0, 2);
+    return event.username?.substring(0, 2) ?? '';
 }

src/events/event/event.spec.ts

@@ -53,5 +53,16 @@ describe('Events', () => {
                 jasmine.arrayContaining([expected])
             );
         });
+
+        it('should return empty string if username is null or undefined', () => {
+            const eventWithoutUsername = {
+                ...fakeEvents[0],
+                username: undefined
+            };
+
+            const results = convertEventsToEventStreamEvents([eventWithoutUsername]);
+
+            expect(results[0].subject.initials).toEqual('');
+        });
     });
 });