feat(frontend): fixup typecheck

Author: rileyhgrant

browser/src/ConstraintTable/ConstraintTable.tsx

@@ -126,7 +126,10 @@ const ConstraintTable = ({ datasetId, geneOrTranscript }: Props) => {
       {['controls', 'non_neuro', 'non_cancer', 'non_topmed'].some((subset) =>
         datasetId.includes(subset)
       ) && <p>Constraint is based on the full gnomAD dataset, not the selected subset.</p>}
-      <GnomadConstraintTable geneFlags={geneOrTranscript.flags} constraint={gnomadConstraint!} />
+      <GnomadConstraintTable
+        geneFlags={isGene(geneOrTranscript) ? (geneOrTranscript as Gene).flags : []}
+        constraint={gnomadConstraint!}
+      />
       {isGene(geneOrTranscript) && (
         <p style={{ marginBottom: 0 }}>
           Constraint metrics based on {transcriptDescription} transcript (