Add details to test_LocationListener_ProgressListener_cancledLoad

[fedejeanne]

Also, use String::isEmpty to check for the size of the location instead of its length

[github-actions]

Test Results

   545 files  + 6     545 suites  +6   28m 18s ⏱️ - 3m 38s
 4 367 tests +37   4 355 ✅ +35   12 💤 +3  0 ❌  - 1 
16 616 runs  +37  16 512 ✅ +35  104 💤 +3  0 ❌  - 1 

Results for commit 76b9673. ± Comparison against base commit 3670670.