Incorrect post url in api calls

[devreltomtom]

in Developer::getRevenueReport()
and Organization::getPrepaidBalanceReport()
Setting always base Url caused problems with incorrect url. The required subpath should be passed to first argument of post() method.

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[mxr576]

@devreltomtom Please restore indention in code and accept the CLA.

[mxr576]

Indention in code should not be changed.