build: cancel screenshot diff if there is no activity (#6957)
build: cancel screenshot diff if there is no activity (#6957)

* build: cancel screenshot diff if there is no activity

* No longer just gives the screenshot diff task 8 minutes to pass, because the run time can vary. Now it just exits the process if the last action in the task takes longer than 6 minutes.
* Instead of just closing the firebase connection, the process will be exited with an error code. Just closing the connection is not helpful and breaks the screenshot diff Web Interface.

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crisbeto/material2,josephperrott/material2,mmalerba/material2,josephperrott/material2,DevVersion/material2,kara/material2,andrewseguin/material2,Eddman/material2,jelbourn/material2,willshowell/material2,tinayuangao/material2,willshowell/material2,fairfaxmedia/material2,mmalerba/material2,Eddman/material2,andrewseguin/material2,emoralesb05/material2,ppham27/material2,Jefiozie/material2,DevVersion/material2,Jefiozie/material2,willshowell/material2,amcdnl/material2,crisbeto/material2,fairfaxmedia/material2,fairfaxmedia/material2,emoralesb05/material2,ChronosWS/material2,amcdnl/material2,jasnoponjatno/material2,jasnoponjatno/material2,jelbourn/material2,shaunak1111/material2,Eddman/material2,angular/components,amcdnl/material2,willshowell/material2,tinayuangao/material2,andrewseguin/material2,crisbeto/material2,josephperrott/material2,ppham27/material2,emoralesb05/material2,shaunak1111/material2,mmalerba/material2,jasnoponjatno/material2,ChronosWS/material2,DevVersion/material2,kara/material2,DevVersion/material2,mmalerba/material2,ppham27/material2,amcdnl/material2,Jefiozie/material2,willshowell/material2,josephperrott/material2,fairfaxmedia/material2,tinayuangao/material2,kara/material2,shaunak1111/material2,emoralesb05/material2,crisbeto/material2,jasnoponjatno/material2,tinayuangao/material2,angular/components,ChronosWS/material2,andrewseguin/material2,jelbourn/material2,tinayuangao/material2,mmalerba/material2,ChronosWS/material2,ppham27/material2,angular/components,DevVersion/material2,jelbourn/material2,Eddman/material2,kara/material2,Jefiozie/material2,fairfaxmedia/material2,ppham27/material2,andrewseguin/material2,amcdnl/material2,Eddman/material2,josephperrott/material2,Jefiozie/material2,shaunak1111/material2,jelbourn/material2,emoralesb05/material2,angular/components