[Workspace]Fix workspace assets page UI bugs

[wanglam]

Description

This PR is for fixing a bunch of UI bugs in the workspace assets page. Here are the fixed list:

• The spacing around the table and search bar should be 16px
• Remove the "Workspace" column and filter
• Add tooltip to "Refresh" icon button
• Change the label of the workspace select field to "Target workspace" and remove the field description
• Add "Close" button to the footer of the resulting message flyout
• Change "Objects" to "Assets" in the "Export" modal (all instances)
• Change "Saved objects" to "Assets" in the Import flyout
• Change "saved objects" to "assets" for the buttons

Issues Resolved

Screenshot

Global assets

Workspace assets

Testing the changes

• Clone branch code and run yarn osd bootstrap --single-version ignore
• Add below configs in config/opensearch_dashboards.yml

savedObjects.permission.enabled: true
workspace.enabled: true
uiSettings:
  overrides:
    'home:useNewHomePage': true
opensearchDashboards.dashboardAdmin.users: ['admin']

• Run yarn start --no-base-path
• Click "View all" in the "Assets" panel
• The global assets should work as screenshot above
• Enter a workspace use left navigation
• Click "View all" in the "Assets" panel
• The workspace assets page should work as screenshot above

Changelog

• fix: [Workspace]Fix workspace assets page UI bugs

Check List

• All tests pass
  • yarn test:jest
  • yarn test:jest_integration
• New functionality includes testing.
• New functionality has been documented.
• Update CHANGELOG.md
• Commits are signed per the DCO using --signoff

[codecov]

Codecov Report

Attention: Patch coverage is 94.44444% with 1 line in your changes missing coverage. Please review.

Project coverage is 64.09%. Comparing base (2213b57) to head (f71e315).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ment_section/objects_table/saved_objects_table.tsx	88.88%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8265   +/-   ##
=======================================
  Coverage   64.09%   64.09%           
=======================================
  Files        3744     3744           
  Lines       88822    88822           
  Branches    13841    13842    +1     
=======================================
+ Hits        56931    56932    +1     
  Misses      31277    31277           
+ Partials      614      613    -1     

Flag	Coverage Δ
Linux_1	30.04% <16.66%> (+<0.01%)	⬆️
Linux_2	58.85% <ø> (ø)
Linux_3	40.34% <6.25%> (+<0.01%)	⬆️
Linux_4	31.57% <93.75%> (+<0.01%)	⬆️
Windows_1	30.06% <16.66%> (+<0.01%)	⬆️
Windows_2	58.80% <ø> (ø)
Windows_3	40.34% <6.25%> (+<0.01%)	⬆️
Windows_4	31.57% <93.75%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[Hailong-am]

do we need to check new home page flag for all those wording change?