Changed required minimum intervals in cold start message (#411)

Required minimum intervals to finish cold start is related to shingle size. This PR adds the shingle size in the computation and puts the result in the cold start message.

Testing done:
1. verified changing shingle size will change the message.

Signed-off-by: Kaituo Li <kaituo@amazon.com>

public/pages/DetectorResults/containers/AnomalyResults.tsx

@@ -66,6 +66,7 @@ import { detectorIsSample } from '../../Overview/utils/helpers';
 import { SampleIndexDetailsCallout } from '../../Overview/components/SampleIndexDetailsCallout/SampleIndexDetailsCallout';
 import { CoreStart } from '../../../../../../src/core/public';
 import { CoreServicesContext } from '../../../components/CoreServices/CoreServices';
+import { DEFAULT_SHINGLE_SIZE } from '../../../utils/constants';
 
 interface AnomalyResultsProps extends RouteComponentProps {
   detectorId: string;
@@ -313,7 +314,8 @@ export function AnomalyResults(props: AnomalyResultsProps) {
               <p>
                 Attempting to initialize the detector with historical data.
                 This initializing process takes approximately 1 minute if
-                 you have data in each of the last 40 consecutive intervals.
+                you have data in each of the last{' '}
+                {32+get(detector, 'shingleSize', DEFAULT_SHINGLE_SIZE)}{' '} consecutive intervals.
               </p>
             </EuiText>
           </EuiFlexGroup>