Fix duplicate nested lambda compilation

[dadhi]

We should avoid both Collect and Compile round for the same lambda expression,
but currently it is not working as intended.

It happens for sure in the test:

• Nested_lambdas_assigned_to_vars

and in others:

• NestedLambdasSharedToExpressionCodeStringTest
• NestedLambdaTests.Given_composed_expr_with_closure_over_2_parameters_used_in_2_levels_of_nested_lambda
• NestedLambdaTests.Given_composed_expr_with_closure_over_2_same_parameters_used_in_2_levels_of_nested_lambda

Add the diagnostics about number of nested lambdas and number of compilations to IDelegateDebugInfo

[dadhi]

Fixed and nice results comparison before and after (look Ratio and Alloc Ratio):

Before

Method	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen0	Gen1	Allocated	Alloc Ratio
LightExpression_with_sub_expressions_CompiledFast	22.57 us	0.442 us	0.862 us	22.26 us	1.00	0.00	1.7090	1.6785	10.52 KB	1.00
Expression_with_sub_expressions_Compiled	517.53 us	10.254 us	27.546 us	503.49 us	22.95	1.36	3.9063	2.9297	28.91 KB	2.75

After

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Gen1	Gen2	Allocated	Alloc Ratio
LightExpression_with_sub_expressions_CompiledFast	21.32 us	0.387 us	0.717 us	1.00	0.00	1.4648	1.4038	0.0305	9 KB	1.00
Expression_with_sub_expressions_Compiled	571.67 us	11.221 us	12.922 us	26.75	1.11	3.9063	2.9297	-	28.47 KB	3.16