Goal: My all worked done from Gmail app. Sign out the Gmail account
Steps:
action: action_type: navigate_back
step_instruction: Go back to the previous screen
action: action_type: click
step_instruction: Click on the Manage your Google Account in the Account section
action: action_type: click
step_instruction: Click on the drop down arrow next to the thomas.blanc1978@gmail.com
action: action_type: click
step_instruction: Click on the Manage accounts on this device 
action: action_type: scroll
direction: down
step_instruction: Scroll down to view more account
action: action_type: click
step_instruction: Click on my gmail account thomas.blanc1978@gmail.com
action: action_type: click
step_instruction: Click on the Remove account button
action: action_type: click
step_instruction: Click on the Remove account next to Cancel