Bump 1.4.2

Build 1.4.2

Bump version 1.4.2-RC1

Build 1.4.2-RC1

Bump 1.4.1

Build 1.4.1

Improve display of validation errors for scripts (ampproject#3722)

* Improve display of validation errors for scripts

* Fix phpcs issues

* Improve validation error summary on index detail page

* Eliminate soft-deprecated use of tag_row_actions filter

* Eliminate unecessary use of sprintf()

Build 1.4.1-RC1

Merge pull request ampproject#3672 from ampproject/bump/1.4.0

Bump 1.4.0 and update readme for Twenty Twenty

Build 1.4.0