I18N: Annotate literals in advisory command

[ppisar]

The comment is extracted by "xgettext -c" and placed to gettext catalogs. It helps the translators not know which words not to translate:

#. Note for translators: "critical" etc. quoted words are
#. literals that should not be translated.
#: commands/advisory/arguments.hpp:155
msgid ""
"Limit to packages in advisories with specified severity. List option. Can be "
"\"critical\", \"important\", \"moderate\", \"low\", \"none\"."
msgstr ""

Fixes: #1159

[rffontenelle]

How about making them placeholders {} instead?

[j-mracek]

LGTM

[ppisar]

Removing the literals from the message and substituting them dynamically would be bad because:

• The message would have to be built at run-time. A static string as it is now is much faster and saves a memory.
• The data structure the message is stored now does not support run-time computations. The text must be ready when compiling the code. Using a formating string would require changing the code.
• The translators could not explain a meaning of the literals in their translations, like:

msgid ""
"Limit to packages in advisories with specified severity. List option. Can be "
"\"critical\", \"important\", \"moderate\", \"low\", \"none\"."
msgstr ""
"Limit to packages in advisories with specified severity. List option. Can be "
"\"critical\" [very serious], \"important\" [serious], \"moderate\" [normal] , \"low\" [unimportant], \"none\" [undefined]."
~~~

Here in English to English translation it does not highlight the problem boldly, but I believe you know what I mean.

[j-mracek]

I am curios whether we should use C_() to add a context for translators instead?

[ppisar]

Translation contexts are for distinguishing two identical messages for a need of different translations. This is not the case. This message only exists at two places dnf5/commands/advisory_shared.hpp and dnf5daemon-client/commands/advisory/arguments.hpp. The messages has the same meaning and use (their code and method name is actually a duplicate), so no artificial context is needed here.