Language server: Add test for diagnostics

[turbolent]

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[codecov-commenter]

Codecov Report

Merging #1233 (1bf0548) into master (4348c5d) will decrease coverage by 0.05%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1233      +/-   ##
==========================================
- Coverage   77.46%   77.41%   -0.06%     
==========================================
  Files         273      273              
  Lines       34764    34823      +59     
==========================================
+ Hits        26929    26957      +28     
- Misses       6760     6791      +31     
  Partials     1075     1075              

Flag	Coverage Δ
unittests	77.41% <ø> (-0.06%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
runtime/convertTypes.go	76.54% <0.00%> (-2.61%)	⬇️
encoding/json/decode.go	71.12% <0.00%> (-2.07%)	⬇️
runtime/interpreter/errors.go	23.20% <0.00%> (-0.19%)	⬇️
encoding/json/encode.go	93.42% <0.00%> (ø)
runtime/interpreter/interpreter.go	89.04% <0.00%> (+<0.01%)	⬆️
runtime/interpreter/primitivestatictype.go	75.23% <0.00%> (+0.93%)	⬆️
types.go	76.92% <0.00%> (+1.51%)	⬆️
runtime/interpreter/simplecompositevalue.go	79.31% <0.00%> (+1.72%)	⬆️

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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit 5090f51
The command go test ./... -run=XXX -bench=. -shuffle=on -count N was used.
Bench tests were run a total of 7 times on each branch.

Results

	old.txt	new.txt
	time/op		delta
RuntimeResourceDictionaryValues-2	17.6ms ± 4%	17.3ms ± 5%	~	(p=0.383 n=7+7)
RuntimeStorageWriteCached-2	146µs ± 3%	148µs ± 4%	~	(p=0.383 n=7+7)
RuntimeFungibleTokenTransfer-2	1.30ms ± 3%	1.48ms ±20%	~	(p=0.318 n=7+7)
NewInterpreter/new_interpreter-2	1.22µs ± 2%	1.22µs ± 1%	~	(p=0.619 n=6+6)
NewInterpreter/new_sub-interpreter-2	2.20µs ± 2%	2.18µs ± 2%	~	(p=0.165 n=7+7)
InterpretRecursionFib-2	2.87ms ± 3%	2.90ms ± 3%	~	(p=0.383 n=7+7)
ContractInterfaceFungibleToken-2	52.1µs ± 3%	50.1µs ± 2%	−3.84%	(p=0.001 n=7+7)
ParseDeploy/decode_hex-2	1.67ms ± 2%	1.55ms ± 3%	−7.00%	(p=0.001 n=7+7)
ParseDeploy/byte_array-2	38.0ms ± 2%	35.3ms ± 3%	−7.17%	(p=0.001 n=7+7)
QualifiedIdentifierCreation/One_level-2	3.71ns ± 4%	3.42ns ± 2%	−7.86%	(p=0.001 n=7+7)
ParseInfix-2	27.2µs ± 2%	24.8µs ± 1%	−8.60%	(p=0.001 n=7+7)
QualifiedIdentifierCreation/Three_levels-2	199ns ± 3%	179ns ± 3%	−9.69%	(p=0.001 n=7+7)
ParseArray-2	25.8ms ± 1%	23.2ms ± 1%	−9.98%	(p=0.001 n=7+6)
ParseFungibleToken-2	538µs ± 2%	478µs ± 4%	−11.14%	(p=0.001 n=7+7)
CheckContractInterfaceFungibleTokenConformance-2	206µs ± 3%	179µs ± 6%	−12.78%	(p=0.001 n=7+7)
	alloc/op		delta
RuntimeResourceDictionaryValues-2	4.33MB ± 0%	4.33MB ± 0%	~	(p=0.383 n=7+7)
RuntimeStorageWriteCached-2	83.7kB ± 0%	83.7kB ± 0%	~	(p=0.385 n=7+6)
RuntimeFungibleTokenTransfer-2	225kB ± 0%	225kB ± 0%	~	(p=0.927 n=7+7)
QualifiedIdentifierCreation/One_level-2	0.00B	0.00B	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	64.0B ± 0%	64.0B ± 0%	~	(all equal)
CheckContractInterfaceFungibleTokenConformance-2	66.4kB ± 0%	66.4kB ± 0%	~	(p=0.053 n=5+7)
ContractInterfaceFungibleToken-2	26.7kB ± 0%	26.7kB ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	680B ± 0%	680B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.02kB ± 0%	1.02kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.21MB ± 0%	1.21MB ± 0%	~	(all equal)
	allocs/op		delta
RuntimeResourceDictionaryValues-2	108k ± 0%	108k ± 0%	~	(p=0.763 n=7+7)
RuntimeStorageWriteCached-2	1.42k ± 0%	1.42k ± 0%	~	(all equal)
RuntimeFungibleTokenTransfer-2	4.38k ± 0%	4.38k ± 0%	~	(p=0.192 n=7+7)
QualifiedIdentifierCreation/One_level-2	0.00	0.00	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	2.00 ± 0%	2.00 ± 0%	~	(all equal)
CheckContractInterfaceFungibleTokenConformance-2	1.07k ± 0%	1.07k ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	458 ± 0%	458 ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	11.0 ± 0%	11.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	30.0 ± 0%	30.0 ± 0%	~	(all equal)
InterpretRecursionFib-2	25.0k ± 0%	25.0k ± 0%	~	(all equal)