perf: change List to array

[TimothyMakkison]

Small change:
Convert ToList call to ToArray call, this is useful for cases where the result collection doesn't contain items letting us use an empty array instead of allocating a new empty List<PrintedNode>[]

Benchmarks timing is inaccurate, memory usage is not

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	Median	Gen0	Gen1	Allocated
Default_CodeFormatter_Tests	148.0 ms	2.95 ms	6.84 ms	147.0 ms	2000.0000	1000.0000	28.76 MB
Default_CodeFormatter_Complex	308.4 ms	11.78 ms	34.00 ms	294.5 ms	4000.0000	2000.0000	47.44 MB