fix: Close spinner if the buffer does not exist

[qoobes]

WHAT

Hide the spinner if the buffer it's targeting does not exist.

WHY

If you close the vertical split before it's done generating you're going to get spammed with errors because the buffer it's trying to access is invalid.

HOW

Use builtin vim functions to check if the buffer that's being targeted is valid, if it isn't hide the spinner.

Screenshots (if appropriate):

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] Linter
• [ ] Tests
• [ ] Review comments
• [x] Security

Note: I'm very very new to lua.

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: a3c9d81983e8a8876ee6734cfb40b40318d684d1

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[jellydn]

Thanks @qoobes LGTM!

[jellydn]

@all-contributors add @gptlang for code,doc

[allcontributors[bot]]

@jellydn

I've put up a pull request to add @gptlang! :tada:

[jellydn]

@all-contributors add @jellydn for code,doc

[allcontributors[bot]]

@jellydn

I've put up a pull request to add @jellydn! :tada:

[jellydn]

@all-contributors add @qoobes for code

[allcontributors[bot]]

@jellydn

I've put up a pull request to add @qoobes! :tada:

[jellydn]

@all-contributors add @ziontee113 for code

[allcontributors[bot]]

@jellydn

I've put up a pull request to add @ziontee113! :tada: