Undo the split sentence in "...because %{reason}" to make text localizable

Problem at a high level:

This error message, that is composed of 2 fragments, when resolved into one sentence on the UI, will create readability and translatability problems in non-English languages. In other words, it will not sound correct in non-English.

msgid "Your comment could not be submitted because %{reason}."

msgid "Maximum number of comments exceeded"

Resolving these fragments into one sentence looks OK in English, but will sound grammatically and syntactically incorrect in non-English languages.

Proposed solution:

The error message should be reformatted into one English sentence. For example: Your comment could not be submitted because maximum number of comments exceeded.

Or, split into 2 sentences and associated with one msgid. For example, Your comment could not be submitted. The maximum number of comments has been exceeded.

And associated code should be refactored, to undo the injecting of %{reason}.

Localizability best practices requirements are described in the following Mozilla resource: https://mozilla-l10n.github.io/documentation/localization/dev_best_practices.html#splitting-and-composing-sentences