(NFC) Version Check Test - Fix multi-user and concurrent execution

(NFC) Version Check Test - Fix multi-user and concurrent execution

This is a small change to the way the tests run. It doesn't change the meaning of the test.

Before
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* Writes example file to `/tmp/versionCheckTestFile.json`.
* File left behind at end of test.
* If two users runs the same test at different times, they could interfere with each other.
* If two processes run the same test at the same time, they could interfere with each other.

After
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* Writes example file to `/tmp/VersionCheck-NNNNNNN/versionCheckTestFile.json`
* Temp folder cleaned up at end
* If two users or two processes run the test, they use separate folders