Playground Persistence Enhancement (fix issue #1787)

[ChengGeng97]

Description

Meant to fix this issue: #1787

Type of change

• Enhancement

How to test

• Open or save a new file. GitHub button text will change to reflect the file name.
• If changes are made in the editor after the latest open or save, the color of the file name text will change to orange. If there are no such unsaved changes, the color of the file name text will be blue.
• Additional dialog to confirm a save for a new file has been removed.

[coveralls]

Pull Request Test Coverage Report for Build 945292967

• 2 of 18 (11.11%) changed or added relevant lines in 5 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.06%) to 30.179%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/features/playground/PlaygroundActions.ts	1	2	50.0%
src/pages/playground/Playground.tsx	0	2	0.0%
src/features/github/GitHubUtils.tsx	0	3	0.0%
src/commons/controlBar/github/ControlBarGitHubButtons.tsx	0	10	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/commons/controlBar/github/ControlBarGitHubButtons.tsx	1	2.78%

Totals
Change from base Build 945210705:	-0.06%
Covered Lines:	3231
Relevant Lines:	9872

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💛 - Coveralls

[martin-henz]

Looks very reasonable.

[martin-henz]

(difficult to test; so much easier to test after deployment, so that's what I will do, and follow up if necessary)