Wiki Style Renderer: Keyboard users need to press Tab twice to reach the text color drop-down

Issue Summary

At the Wiki Style renderer menu, Keyboard users need to press the key "tab" twice when moving from left to the right to select the drop-down menu for the text colors.

When using the keys "Shift"+"tab" to move from right to the left, keyboard users need to press twice to move from the Text Color to the underline icon. 

Steps to Reproduce

• Reach any issue, for instance, this issue https://jira.atlassian.com/browse/JSWSERVER-21387;
• Add a new comment and select the shift+tab to reach the menu of options;
• Keep pressing shift+tab moving from right to the left until reaching the text color button;
  
• Press <space bar> to observe the menu of options;
  

• Press shift+tab again to reach the Underline button;

Expected Results

• The cursor would move to the Underline button

Actual Results

• Observe that it first accessed the text color icon;
  
• We do need to press shift+tab again to reach the Underline button.

Workaround

When moving the tab from left to the right, we need to press the tab twice to be able to reach the drop-down menu for the text color.

When moving the tab from right to the left, we need to press the tab twice to reach the underline button.