[go][api] Fix error: 'undeclared name: localVarFile'

[wy-z]

Signed-off-by: weiyang weiyang.ones@gmail.com

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Description of the PR

[go][api] Fix error: 'undeclared name: localVarFile'

'localVarFile' whill be undeclared when the file param is required.

[wy-z]

It seems that #382 is better ~

[wing328]

@wy-z thanks for the PR.

#382 has been merged into master. Please check out the latest master to see if it solves the problem for you.