Don't panic when function parameters share names

[AnnikaCodes]

This PR works on #823.

It changes the following:

• Adds an allow_name_reuse parameter to EnvironmentRecordTrait::create_mutable_binding
• Fixes the panic in S10.2.1_A3.js from the test262 test suite
• Allows the following code to run correctly without crashing Boa:

function test(x, x) {
    return x;
}
test(0, 1); // should return `1`

[codecov]

Codecov Report

Merging #1017 (e424fdb) into master (4625c1a) will increase coverage by 0.01%.
The diff coverage is 75.00%.

@@            Coverage Diff             @@
##           master    #1017      +/-   ##
==========================================
+ Coverage   60.10%   60.11%   +0.01%     
==========================================
  Files         167      167              
  Lines       11142    11145       +3     
==========================================
+ Hits         6697     6700       +3     
  Misses       4445     4445              

Impacted Files	Coverage Δ
boa/src/environment/object_environment_record.rs	23.72% <0.00%> (ø)
.../src/environment/declarative_environment_record.rs	41.11% <66.66%> (+0.66%)	⬆️
boa/src/environment/function_environment_record.rs	34.78% <66.66%> (+0.57%)	⬆️
boa/src/environment/global_environment_record.rs	21.05% <75.00%> (ø)
boa/src/builtins/function/mod.rs	74.74% <100.00%> (ø)
boa/src/environment/lexical_environment.rs	67.61% <100.00%> (+0.31%)	⬆️
boa/src/object/gcobject.rs	65.86% <100.00%> (ø)

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[Razican]

Test262 conformance changes:

Test result	master count	PR count	difference
Total	78,493	78,493	0
Passed	20,882	20,884	+2
Ignored	15,585	15,585	0
Failed	42,026	42,024	-2
Panics	388	386	-2
Conformance	26.60	26.61	+0.00%

[Razican]

Thanks for the fix! I think this looks pretty good :)