Minor text changes in mention failure messages.
Minor text changes in mention failure messages.

To address newest text changes discussed in the ticket and preparation
for the bigger bundleing.

Bug: T140224
Change-Id: Ie532e9c918f24e7ea241aaaca18169b6021cf304

wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo