Run Test Workflow only if Go code was changed

[pofl]

I've never worked with GitHub actions so I hope this has been set up correctly. What do you think about this change?

[codecov]

Codecov Report

Merging #1637 (31599cf) into master (28ec3f7) will decrease coverage by 0.93%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1637      +/-   ##
==========================================
- Coverage   85.28%   84.35%   -0.94%     
==========================================
  Files          28       28              
  Lines        2216     1911     -305     
==========================================
- Hits         1890     1612     -278     
+ Misses        212      189      -23     
+ Partials      114      110       -4     

Impacted Files	Coverage Δ
middleware/proxy.go	60.97% <0.00%> (-5.37%)	⬇️
middleware/method_override.go	80.95% <0.00%> (-3.67%)	⬇️
middleware/redirect.go	85.00% <0.00%> (-3.24%)	⬇️
context.go	86.59% <0.00%> (-3.13%)	⬇️
middleware/basic_auth.go	65.62% <0.00%> (-2.95%)	⬇️
middleware/util.go	88.88% <0.00%> (-1.74%)	⬇️
response.go	85.18% <0.00%> (-1.66%)	⬇️
middleware/cors.go	77.94% <0.00%> (-1.52%)	⬇️
echo.go	84.75% <0.00%> (-1.18%)	⬇️
middleware/key_auth.go	66.66% <0.00%> (-1.13%)	⬇️
... and 18 more

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[lammel]

Looks good to me.

Please also add go.mod and for tests the _fixture dir to ensure tests are rerun also when fixtures change. Both change rarely.

[lammel]

Guess we'll see if it works out as expected.
Thanks @pofl