Add a settings dropdown to GLQL views

What does this MR do and why?

Add a settings dropdown to GLQL views

Add a new settings dropdown to all GLQL views containing three options: View source, Copy source and Copy contents

Additionally this MR:

• Preserves the collapsible state of GLQL views
• Moves footer and actions slots into a shared component that is shared between list and table views
• Couple of styling fixes

Changelog: added

Related issues

• Improve copy/pasting of GLQL tables (#491287 - closed)
• Show glql query next to the rendered block (#483293 - closed)

Screenshots or screen recordings

Description	After
Actions dropdown
View source modal

How to set up and validate locally

1. In an issue, create the following GLQL blocks:

   ```glql
   title: No issues
   description: None of the issues!
   display: list
   query: weight = 13
   fields: title, created, author, assignees, updated, labels, weight, epic
   ```
   
   ```glql
   title: No issues
   description: None of the issues!
   display: table
   query: weight = 13
   fields: title, created, author, assignees, updated, labels, weight, epic
   ```
   
   ```glql
   title: All issues
   description: All the issues!
   display: orderedList
   query: weight != 13
   fields: title, created, author, assignees, updated, labels, weight, epic
   ```
   
   ```glql
   title: All issues
   description: All the issues!
   display: table
   query: weight != 13
   fields: title, created, author, assignees, updated, labels, weight, epic
   ```

The first two blocks should list nothing and the last two should list all issues in the project. When there are no issues, or the query is being loaded, the "Copy contents as Markdown" option is unavailable:

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