Desktop: `Find` up/down arrows and X out of line vertically

Description

Environment: 4.5-rc0 desktop app with electron 7 upgrade, macOS Catalina & Mojave, Win10 and Win7
Not a regression found on previous desktop versions.

Steps:
1) Use keyboard shortcut cmd+F to open Find search bar

Expected: Arrows and X to be centered vertically within the buttons

Actual: Icons are not vertically aligned. See image.
The shading of the buttons is also confusing, as the arrows appear actionable even when the search is empty. Needs UX input.

QA Test Steps

None

Mana

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Assignee

Unassigned

QA Assignee

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Reporter

Jelena Gilliam

Epic Link

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Fix versions

Mattermost Team

Apps

Sprint

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Labels

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QA Testing Areas

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GitHub Issue

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Components

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Severity

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