Revert "Allow the Emulator user to specify a User ID (#1422)"

[justinwilaby]

This reverts commit 2c6a4cf.

[coveralls]

Pull Request Test Coverage Report for Build 2398

• 5 of 11 (45.45%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.03%) to 55.463%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
packages/app/client/src/ui/editor/emulator/emulator.tsx	5	11	45.45%

Files with Coverage Reduction	New Missed Lines	%
packages/app/client/src/ui/editor/emulator/emulator.tsx	1	73.37%

Totals
Change from base Build 2390:	-0.03%
Covered Lines:	4897
Relevant Lines:	8320

---

💛 - Coveralls

[JuanAr]

@justinwilaby should we reopen #1344?

[cwhitten]

Hi @JuanAr - Justin's in-flight work in #1400 had problems reconciling with some of the changes made in this diff, so we reverted it in the hopes that when his branch lands @Aliandi can reissue the pull request against master again.