Fix JSON config upload

[robertalv]

Description

Fixed application upload to json

Motivation and Context

Allows Upload Google API Credentials File to be selected.

How To Test This

Test with text/plain and then test with application/json,.json

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Final checklist

• [x] My code follows the code style of this project found here.
• [ ] My change requires a change to the documentation.
• [x] I have read the How to Contribute guidelines.

[robertalv]

Signed CLAHub.

[Dillon-Brown]

Hi @robertalv, would you be able to remake this for the hotfix-7.10.x branch? thanks.

[SuiteBot]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
5 out of 9 committers have signed the CLA.

:white_check_mark: samus-aran
:white_check_mark: JimMackin
:white_check_mark: cameronblaikie
:white_check_mark: Dillon-Brown
:white_check_mark: urdhvatech
:x: gymad
:x: janderson
:x: code-ph0y
:x: robertalv

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