PULL_REQUEST_TEMPLATE.md: update to match main repo

.github/PULL_REQUEST_TEMPLATE.md

@@ -6,10 +6,6 @@ After making all changes to the cask:
 - [ ] `brew cask style --fix {{cask_file}}` reports no offenses.
 - [ ] The commit message includes the cask’s name and version.
 
-Additionally, if **updating only the `sha256`**:
-
-- [ ] I verified this change is legitimate [<sup>How do I do that?</sup>][version-checksum] and **am providing confirmation below**:
-
 Additionally, if **adding a new cask**:
 
 - [ ] Named the cask according to the [token reference].