Tempo: Show <1ms when durationMs not in response (#85267)

* Show <1ms when durationMs not in response

* Update tests

public/app/plugins/datasource/tempo/resultTransformer.test.ts

@@ -79,6 +79,7 @@ describe('createTableFrameFromTraceQlQuery()', () => {
     expect(frame.fields[4].name).toBe('traceDuration');
     expect(frame.fields[4].type).toBe('number');
     expect(frame.fields[4].values[2]).toBe(44);
+    expect(frame.fields[4].values[1]).toBe('<1ms');
     // Subframes field
     expect(frame.fields[5].name).toBe('nested');
     expect(frame.fields[5].type).toBe('nestedFrames');

public/app/plugins/datasource/tempo/resultTransformer.ts

@@ -468,7 +468,7 @@ function transformToTraceData(data: TraceSearchMetadata) {
   return {
     traceID: data.traceID,
     startTime: parseInt(data.startTimeUnixNano!, 10) / 1000000,
-    traceDuration: data.durationMs,
+    traceDuration: data.durationMs || '<1ms',
     traceService: data.rootServiceName || '',
     traceName: data.rootTraceName || '',
   };
@@ -915,7 +915,7 @@ interface TraceTableData {
   spanID?: string;
   startTime?: number;
   name?: string;
-  traceDuration?: number;
+  traceDuration?: number | string;
 }
 
 function transformSpanToTraceData(span: Span, spanSet: Spanset, trace: TraceSearchMetadata): TraceTableData {

public/app/plugins/datasource/tempo/testResponse.ts

@@ -2368,7 +2368,6 @@ export const traceQlResponse = {
       rootServiceName: 'lb',
       rootTraceName: 'HTTP Client',
       startTimeUnixNano: '1643342166678000000',
-      durationMs: 93,
       spanSets: [
         {
           attributes: [