[Dropdown] [Fluent & Indigo] Icon sizes should be aligned to the ones in WebC and in Design Kit

[yradoeva]

Is your feature request related to a problem? Please describe.

The icons of the dropdown items have different sizes compared to WebC and Figma Design.

Describe the solution you'd like

According to last discussed and in order to be aligned with WebC and Design Kit, the icons of the dropdown items should be:

For Fluent

• Small 18x18px in the three dropdown sizes L, M and S

For Indigo

• Small 14x14px for S dropdown
• Medium 16x16px for M and L dropdown

Additional context

Link to Figma Design Kit - Fluent

Indigo