perf: prevent boxing SyntaxTokenList by calling ToArray earlier

[TimothyMakkison]

Prevent boxing SyntaxTokenList by moving the ToArray call to be earlier.
Renamed to modifierArray to reflect the fact its not sorted yet, and later create a local variable called sortedModifiers

Benchmarks - small memory saving timing is inaccurate

Before

Method	Mean	Error	StdDev	Median	Gen0	Gen1	Gen2	Allocated
Default_CodeFormatter_Tests	198.9 ms	9.40 ms	26.98 ms	202.2 ms	2000.0000	1000.0000	-	28.8 MB
Default_CodeFormatter_Complex	336.0 ms	7.01 ms	20.23 ms	325.7 ms	5000.0000	2500.0000	500.0000	47.64 MB

After

Method	Mean	Error	StdDev	Gen0	Gen1	Gen2	Allocated
Default_CodeFormatter_Tests	218.6 ms	20.83 ms	61.08 ms	2000.0000	1000.0000	-	28.77 MB
Default_CodeFormatter_Complex	300.4 ms	5.94 ms	10.25 ms	5000.0000	3000.0000	1000.0000	47.42 MB