Reduce environment allocations

[raskad]

This PR builds on #3988 and removes runtime environment allocations when possible.
All three commits can be reviewd independently. I just put them all together here, because they depend on each other anyways.

Running the benchmarks did not show a big reduction in execution time, but this should reduce memory usage since we can skip and reduce size of allocations.

• Skip environment creation when all bindings in the scope are local
• Skip environment creation when possible for arrow functions
• Do not allocate space for local bindings in runtime environments

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	48,494	48,494	0
Passed	43,609	43,609	0
Ignored	1,500	1,500	0
Failed	3,385	3,385	0
Panics	0	0	0
Conformance	89.93%	89.93%	0.00%

[HalidOdat]

Nice work! Looks great to me! :)