Fix compatibility with JSON <4 (specifically perl-JSON-2.59-2.el7)

[jankratochvil]

hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this) at .../Tesla/API.pm line 124.

[coveralls]

Pull Request Test Coverage Report for Build 2079786574

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 1 (0.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 19.835%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
lib/Tesla/API.pm	0	1	0.0%

Totals
Change from base Build 2072721434:	0.0%
Covered Lines:	48
Relevant Lines:	242

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💛 - Coveralls