Add codecov config

[turbolent]

Description

• Require increasing coverage for all code (auto target; up to 5% variance)
• Require full coverage for new code

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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 #1553 (20f9304) into master (6075ef4) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1553   +/-   ##
=======================================
  Coverage   74.72%   74.72%           
=======================================
  Files         289      289           
  Lines       55633    55633           
=======================================
  Hits        41569    41569           
  Misses      12563    12563           
  Partials     1501     1501           

Flag	Coverage Δ
unittests	74.72% <ø> (ø)

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

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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit 6075ef4
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
ParseInfix-2	10.1µs ± 2%	10.3µs ± 3%	+1.62%	(p=0.038 n=6+7)
RuntimeFungibleTokenTransfer-2	1.72ms ± 5%	1.48ms ±26%	~	(p=0.101 n=6+7)
RuntimeResourceDictionaryValues-2	17.0ms ± 3%	16.9ms ± 2%	~	(p=0.383 n=7+7)
ParseFungibleToken-2	225µs ± 3%	229µs ± 2%	~	(p=0.165 n=7+7)
ParseArray-2	17.8ms ± 7%	17.8ms ± 6%	~	(p=1.000 n=7+7)
ParseDeploy/byte_array-2	28.5ms ± 4%	29.7ms ± 5%	~	(p=0.128 n=7+7)
ParseDeploy/decode_hex-2	1.43ms ± 1%	1.43ms ± 1%	~	(p=0.902 n=7+7)
QualifiedIdentifierCreation/One_level-2	3.25ns ± 3%	3.23ns ± 3%	~	(p=1.000 n=7+7)
QualifiedIdentifierCreation/Three_levels-2	176ns ± 2%	176ns ± 1%	~	(p=0.972 n=6+7)
ContractInterfaceFungibleToken-2	48.4µs ± 2%	49.2µs ± 2%	~	(p=0.073 n=6+7)
CheckContractInterfaceFungibleTokenConformance-2	163µs ± 3%	165µs ± 1%	~	(p=0.097 n=7+7)
InterpretRecursionFib-2	3.30ms ± 2%	3.30ms ± 3%	~	(p=0.805 n=7+7)
NewInterpreter/new_interpreter-2	1.40µs ± 2%	1.40µs ± 1%	~	(p=1.000 n=7+6)
NewInterpreter/new_sub-interpreter-2	2.75µs ± 3%	2.76µs ± 1%	~	(p=0.879 n=7+7)
	alloc/op		delta
RuntimeFungibleTokenTransfer-2	273kB ± 0%	273kB ± 0%	~	(p=1.000 n=7+7)
RuntimeResourceDictionaryValues-2	4.05MB ± 0%	4.05MB ± 0%	~	(p=0.456 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)
ContractInterfaceFungibleToken-2	26.6kB ± 0%	26.6kB ± 0%	~	(p=1.000 n=7+7)
CheckContractInterfaceFungibleTokenConformance-2	66.2kB ± 0%	66.2kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.26MB ± 0%	1.26MB ± 0%	~	(p=0.385 n=7+6)
NewInterpreter/new_interpreter-2	848B ± 0%	848B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.34kB ± 0%	1.34kB ± 0%	~	(all equal)
	allocs/op		delta
RuntimeFungibleTokenTransfer-2	4.54k ± 0%	4.54k ± 0%	~	(p=0.318 n=5+7)
RuntimeResourceDictionaryValues-2	102k ± 0%	102k ± 0%	~	(p=0.869 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)
ContractInterfaceFungibleToken-2	458 ± 0%	458 ± 0%	~	(all equal)
CheckContractInterfaceFungibleTokenConformance-2	1.07k ± 0%	1.07k ± 0%	~	(all equal)
InterpretRecursionFib-2	26.2k ± 0%	26.2k ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	13.0 ± 0%	13.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	40.0 ± 0%	40.0 ± 0%	~	(all equal)