[EuiSuperDatePicker] Excessive space between prepend button icons

[MichaelMarcialis]

Describe the bug
In the latest version of EUI, I noticed that there was an excessive amount of space between the prepend button icons in the EuiSuperDatePicker component. I believe this is occurring because there is both a right margin applied to the first icon and there is now a new gap property being used in EuiButtonEmpty components (whereas previously, it was just the right margin).

Impact and severity
I'm not sure if it affect components beyond the EuiSuperDatePicker, but the issue is visible everywhere that component is in use in Kibana.

Environment and versions

• EUI version: 88.2.0

To Reproduce
View the EuiSuperDatePicker anywhere in Kibana (such as Discover).

Expected behavior
I expect the space between icons to not be so wide.

Screenshots
Previously:

Now: