Fix testBasicPostPublish UI Test

[illusaen]

UI test EditorGutenbergTests-testBasicPostPublish was breaking because test was trying to tap image block after adding it to pop up the bottom sheet, whereas now the bottom sheet seems to pop up automatically after adding the block. Fixed by removing the tap (this is the only test that uses that function).

To test:
Run all UI tests

SS

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding unit tests for my changes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[peril-wordpress-mobile]

You can trigger optional UI/connected tests for these changes by visiting CircleCI here.

[peril-wordpress-mobile]

You can trigger an installable build for these changes by visiting CircleCI here.

[cameronvoell]

Thanks for the fix and for troubleshooting this issue! 🙇