Add tests for linking to already linked paths

[SupunS]

Work towards #1257

Description

This PR add some tests to verify the current behavior of creating links to already linked paths.

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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 #1416 (b96c430) into master (1939cc7) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1416   +/-   ##
=======================================
  Coverage   73.08%   73.08%           
=======================================
  Files         280      280           
  Lines       38952    38952           
=======================================
  Hits        28469    28469           
  Misses       9039     9039           
  Partials     1444     1444           

Flag	Coverage Δ
unittests	73.08% <ø> (ø)

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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit 95e70f9
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Results

	old.txt	new.txt
	time/op		delta
RuntimeResourceDictionaryValues-2	14.0ms ± 2%	14.0ms ± 2%	~	(p=0.620 n=7+7)
RuntimeFungibleTokenTransfer-2	1.17ms ±28%	1.13ms ±35%	~	(p=0.620 n=7+7)
ParseArray-2	12.9ms ± 9%	12.4ms ± 1%	~	(p=0.209 n=7+7)
ParseDeploy/byte_array-2	20.4ms ± 9%	19.7ms ± 1%	~	(p=0.073 n=7+7)
ParseDeploy/decode_hex-2	1.15ms ± 1%	1.17ms ± 3%	~	(p=0.097 n=7+7)
ParseFungibleToken-2	182µs ± 1%	182µs ± 1%	~	(p=0.731 n=6+7)
ParseInfix-2	9.65µs ± 1%	9.94µs ±11%	~	(p=0.620 n=7+7)
QualifiedIdentifierCreation/One_level-2	2.34ns ± 0%	2.34ns ± 0%	~	(p=0.679 n=7+6)
QualifiedIdentifierCreation/Three_levels-2	140ns ± 0%	140ns ± 1%	~	(p=0.362 n=7+6)
CheckContractInterfaceFungibleTokenConformance-2	135µs ± 5%	130µs ± 1%	~	(p=0.073 n=7+6)
ContractInterfaceFungibleToken-2	39.3µs ± 2%	39.3µs ± 1%	~	(p=1.000 n=7+7)
NewInterpreter/new_interpreter-2	1.05µs ± 1%	1.05µs ± 0%	~	(p=1.000 n=7+6)
NewInterpreter/new_sub-interpreter-2	2.09µs ± 1%	2.09µs ± 1%	~	(p=0.818 n=6+6)
InterpretRecursionFib-2	2.40ms ± 4%	2.37ms ± 2%	~	(p=0.836 n=7+6)
	alloc/op		delta
RuntimeResourceDictionaryValues-2	4.05MB ± 0%	4.05MB ± 0%	~	(p=0.259 n=7+7)
RuntimeFungibleTokenTransfer-2	278kB ± 0%	278kB ± 0%	~	(p=0.259 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	66.2kB ± 0%	66.2kB ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	26.6kB ± 0%	26.6kB ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	768B ± 0%	768B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.24kB ± 0%	1.24kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.24MB ± 0%	1.24MB ± 0%	~	(p=0.450 n=7+7)
	allocs/op		delta
RuntimeResourceDictionaryValues-2	102k ± 0%	102k ± 0%	~	(p=0.185 n=7+7)
RuntimeFungibleTokenTransfer-2	4.62k ± 0%	4.62k ± 0%	~	(p=0.298 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	12.0 ± 0%	12.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	38.0 ± 0%	38.0 ± 0%	~	(all equal)
InterpretRecursionFib-2	25.0k ± 0%	25.0k ± 0%	~	(all equal)

[turbolent]

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