Bugzilla

### Steps to reproduce
1. Build Fenix with a custom mozconfig like `MOZCONFIG=mySpecial.mozconfig ./mach build`
2. Run tests on that build `MOZCONFIG=mySpecial.mozconfig ./mach gv-junit blabla`, observe the correct object dir and build config being used by examining the logs and/or adding assertions to the test
3. No try running the tests with your regular mozconfig  `./mach gv-junit blabla`

### Expected behavior
observe it now uses the object dir and build config for the regular `mozconfig` build

### Actual behavior
observe it still uses the object dir and build config for the `mySpecial.mozconfig` build

### Any additional information?
Commenting out [these lines](https://searchfox.org/mozilla-central/source/build.gradle#334-338) helped fix the issue

### Steps to reproduce
1. Build Fenix with a custom mozconfig like `MOZCONFIG=mySpecial.mozconfig ./mach build`
2. Run tests on that build `MOZCONFIG=mySpecial.mozconfig ./mach gv-junit blabla`, observe the correct object dir and build config being used by examining the logs and/or adding assertions to the test
3. No try running the tests with your regular mozconfig  `./mach gv-junit blabla`

### Expected behavior
observe it now uses the object dir and build config for the regular `mozconfig` build

### Actual behavior
observe it still uses the object dir and build config for the `mySpecial.mozconfig` build

### Any additional information?
The issue could not be fixed by rebuilding, resetting the emulator, clobbering the build, bootstraping, restarting the emulator, etc.
Commenting out [these lines](https://searchfox.org/mozilla-central/source/build.gradle#334-338) helped fix the issue