Reduce `compile` translation checks from ERROR to WARNING

[SlowMo24]

Problem

Some translation warnings are false positives.
E.g. 10% of will be recognised as a placeholder (% d). If the translation is 10% der, babel compile will say incompatible format for placeholder 1: 'o' and 'd' are not compatible.

This is then raised as error and the command exits with status: 1. This prevents e.g. running the command during docker image build.

Wish

Even though the exit status is 0 the command succeeds in correctly compiling the .po to a valid .mo file.
The compile command should therefore exit with status 0 and only issue a warning about the problematic translations.

Workaround

Append ; exit 0 to the command to force success.