fix(FAB): add small size style

[sumj25]

What kind of change does this PR introduce?

Fix Fab button with title size bug.

Summary
Fab button with the title does not change on size small. Fix this issue.

Other information

[codecov]

Codecov Report

Merging #3322 (d069ad5) into next (48609e8) will increase coverage by 0.02%.
The diff coverage is 100.00%.

❗ Current head d069ad5 differs from pull request most recent head 8681197. Consider uploading reports for the commit 8681197 to get more accurate results

@@            Coverage Diff             @@
##             next    #3322      +/-   ##
==========================================
+ Coverage   79.93%   79.96%   +0.02%     
==========================================
  Files          88       88              
  Lines        1660     1662       +2     
  Branches      729      731       +2     
==========================================
+ Hits         1327     1329       +2     
  Misses        328      328              
  Partials        5        5              

Impacted Files	Coverage Δ
packages/base/src/FAB/FAB.tsx	100.00% <100.00%> (ø)

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[arpitBhalla]

Thanks for your contribution 🎉