[#1092] Enhance metric form UI

[Mazen050]

Closes #1092

This PR Enhances the look of the metric form UI by introducing 2 individual boxs one for postgres version number and the other for sql, with another button to add New SQL.

Examples of how it looks:

Also versions dropdown is editable and can be used to add a new versions, and it also successfully retrieves older metric sql from backend.

[coveralls]

Pull Request Test Coverage Report for Build 21963883272

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 76.834%

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Totals
Change from base Build 21924096081:	0.0%
Covered Lines:	4179
Relevant Lines:	5439

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💛 - Coveralls

[0xgouda]

Thanks, will take a look tomorrow.

[Mazen050]

Please note that I have added a TODO in the form to restrict input to numbers and dots maybe in the future or maybe in this PR depends if it's needed or not.

[Mazen050]

I have made the version input allow only numbers and dots.

[pashagolub]

thanks for working on this! I have doubts if such UI is reasonably good for the current metrics that are usually several screens long. From the UX point of view it's impossible to make any sane actions with such a layout and lack of syntax highlightning

[Mazen050]

Would making the text area bigger be any better? Currently it starts with 3 rows and expands to 12 rows and then it changes to scrolling.

So we can change the number of max rows or we can make the sql text area wider too since the version input doesn't need that much space.

About syntax highlighting we could use something like a codemirror component instead of the text area.