Tech stack: Go: add Interfaces section

[qdm12]

No description provided.

[render]

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[mpetrunic]

@qdm12 Might wanna add some go devs in company to review?

[kalambet]

@qdm12 could you maybe please elaborate this section even more? Maybe add examples to those 3 paths and some explanation.
And the ideal would be to refer the particular article or a section/post from go.dev.

[noot]

curious about the reasoning for this? specifically that an interface should only have 1 or 2 methods?

[noot]

overall looks good, just one comment/question

[EclesioMeloJunior]

Would be nice to assert whether or not myInterface is of the *myImplementation

Suggested change

	value := myInterface.(*myImplementation).GetValue()
	impl, ok := myInterface.(*myImplementation)
	assert.True(t, ok)
	value := impl.GetValue()

[qdm12]

Not really, since it's a test you know in advance what implementation it is. And if not, panicing in the test is fine I'd say.

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