fix(formula): BI-5959 apply mutations before adding formula to global dimensions during validation

[KonstantAnxiety]

Allows to use constant math expressions (e.g. 1 / 2 * 365) in measures used in window functions, which previously resulted in ERR.DS_API.FORMULA.VALIDATION.AGG.INCONSISTENT validation error

This change should also be virtually free in terms of performance thanks to stage caching

datalens-backend/lib/dl_query_processing/dl_query_processing/compilation/formula_compiler.py

Lines 283 to 290 in 62ce5bf

	def implements_stage(stage: ProcessingStage) -> Callable[[StageProcType], StageProcType]:
	"""
	A parameterized decorator.
	Mark a ``FormulaCompiler`` method as an implementation of a certain formula processing stage.
	This adds the enabling of various caches and error handlers needed to optimize
	formula generation and validation.
	"""