[Multiple Datasource]update no data source text font and button size

[yujin-emma]

Description

1. Change the text font to small
2. Change the footer button to small

Issues Resolved

#6548

Screenshot

Testing the changes

Changelog

• skip

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

[github-actions]

ℹ️ Manual Changeset Creation Reminder

Please ensure manual commit for changeset file 6549.yml under folder changelogs/fragments to complete this PR.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 33.00%. Comparing base (d2d410b) to head (75911d4).
Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6549      +/-   ##
==========================================
+ Coverage   32.93%   33.00%   +0.06%     
==========================================
  Files        2260     2262       +2     
  Lines       45769    45824      +55     
  Branches     7200     7213      +13     
==========================================
+ Hits        15075    15122      +47     
- Misses      29984    29989       +5     
- Partials      710      713       +3     

Flag	Coverage Δ
Linux_1	?
Windows_1	33.00% <ø> (?)

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