Make the build work with -Wformat=2

[davidben]

The -Wformat=2 macro requires every format string either be a string literal, or a parameter that was tagged with the format attribute. The upshot is that it expects every printf function to be marked, or you get warnings like this:

src/console_reporter.cc:104:23: error: format string is not a string literal [-Werror,-Wformat-nonliteral]
  104 |   out << FormatString(fmt, args);
      |                       ^~~

Marking such things is generally worthwhile since it turns on error-checking within the library, so fill in the missing ones.

Tested with:

bazelisk build --copt=-Werror --copt=-Wformat=2 :all

[LebedevRI]

Should this diagnostic be enabled in CMake build then, otherwise things can regress back?

[davidben]

Figured I'd defer to the project maintainers on that. I noticed this because we set this diagnostic in BoringSSL and (for now, but I'm considering changing this) the way we set our diagnostics hits dependencies. But I think this PR makes sense to merge either way, so I figure that can be a separate decision.

[LebedevRI]

Figured I'd defer to the project maintainers on that.

That was the gist of my comment, yes. Aka, let's enable it or it will break again.

I noticed this because we set this diagnostic in BoringSSL and (for now, but I'm considering changing this) the way we set our diagnostics hits dependencies. But I think this PR makes sense to merge either way, so I figure that can be a separate decision.

[davidben]

Added to CMake and Bazel builds.

[dmah42]

lovely. thank you.

[LebedevRI]

@dmah42 you beat me to it.
@davidben thank you!