Increase coverage in MultilayerQG

[navidcy]

this PR adds a test for a 3-layer problem. This way line

GeophysicalFlows.jl/src/multilayerqg.jl

Lines 144 to 146 in 7ab52d1

	for j = 2:nlayers-1
	Qy[:, :, j] = @. beta - Uyy[:, :, j] - Fp[j]*( U[:, :, j+1] - U[:, :, j] ) - Fm[j-1]*( U[:, :, j-1] - U[:, :, j] )
	end

is tested.

[glwagner]

Beautiful

[codecov]

Codecov Report

Merging #32 into master will increase coverage by 0.19%.
The diff coverage is 81.81%.

@@            Coverage Diff             @@
##           master      #32      +/-   ##
==========================================
+ Coverage   98.44%   98.63%   +0.19%     
==========================================
  Files           6        6              
  Lines         513      513              
==========================================
+ Hits          505      506       +1     
+ Misses          8        7       -1

Impacted Files	Coverage Δ
src/multilayerqg.jl	96% <81.81%> (+0.57%)	⬆️

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[coveralls]

Pull Request Test Coverage Report for Build 277

• 9 of 11 (81.82%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 98.635%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/multilayerqg.jl	9	11	81.82%

Totals
Change from base Build 270:	0.2%
Covered Lines:	506
Relevant Lines:	513

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💛 - Coveralls