fix: LEAP-1449: Don't highlight instructions button

[hlomzik]

Instructions button had a weird styling in some conditions.

When you open editor and instructions are displayed ahead — the button becames primary and primary style for icon buttons should definitely be improved.

But if you open instructions modal during your work the style is good, because Actions don't use observer(), so changes in store don't affect it.

Also couple of files connected to buttons usage in different streams are removed as not used.

PR fulfills these requirements

• Tests for the changes have been added/updated (for bug fixes/features)
• Docs have been added/updated (for bug fixes/features)
• Best efforts were made to ensure docs/code are concise and coherent (checked for spelling/grammatical errors, commented out code, debug logs etc.)
• Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

• Product design
• Backend (Database)
• Backend (API)
• Frontend

Does this PR introduce a breaking change?

• Yes, and covered entirely by feature flag(s)
• Yes, and covered partially by feature flag(s)
• No
• Not sure (briefly explain the situation below)

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