fix(explorer): avoid showing results of names with no linked address (#8404)

# Description of change

When searching for a valid name with unset address, the explorer shows a
blank result, which redirects to an invalid page if you click on it.

## Links to any relevant issues

Fixes #8395 

## How the change has been tested

- [ ] Basic tests (linting, compilation, formatting, unit/integration
tests)
- [ ] Patch-specific tests (correctness, functionality coverage)
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have checked that new and existing unit tests pass locally with
my changes

Co-authored-by: Marc Espin <[email protected]>

Author: VmMad

apps/explorer/src/hooks/useSearch.ts

@@ -82,7 +82,7 @@ const getResultsForAddress = async (
     if (iotaNamesClient && isNamesEnabled && isValidIotaName(query)) {
         const nameRecord = await iotaNamesClient.getNameRecord(query.toLowerCase());
 
-        if (!nameRecord) return null;
+        if (!nameRecord || !nameRecord.targetAddress) return null;
 
         return [
             {