Don't discard [[nodiscard]] result of clamping npc attributes

[akrieger]

Summary

Bugfixes "Properly clamp npc personality traits"

Purpose of change

NPC personality traits are supposed to stay within a set range, but there was a bug in the clamp logic and so they were not. This is how to get nuclear Ghandi.

Describe the solution

Store the result of std::clamp to the variable being clamped.

Describe alternatives you've considered

Testing

CI.

Additional context

[akrieger]

Comes from #70314.

[inogenous]

Maybe we should also annotate cata_utility.h clamp as [[nodiscard]], or just one day deprecate it in favor of std::clamp.

Cataclysm-DDA/src/cata_utility.h

Lines 216 to 224 in 60a7d08

	/**
	* Clamp first argument so that it is no lower than second and no higher than third.
	* Does not check if min is lower than max.
	*/
	template<typename T>
	constexpr T clamp( const T &val, const T &min, const T &max )
	{
	return std::max( min, std::min( max, val ) );
	}

[RenechCDDA]

Oh that's embarrassing. Yeah this is what we want.

[RenechCDDA]

or just one day deprecate it in favor of std::clamp.

As far as I can see, cata::clamp only exists because std::clamp was not available at the time. We didn't move to C++17 (which introduced std::clamp) until #64152 (this year). So yes this is just infrastructure work that should be done at some point.