BASW-379: Fix CiviCRM action item icons

[igorpavlov-zz]

Overview

This PR fixes the issue with actions icons in CiviCRM.

Before

After

Technical description

The problem is at scss/civicrm/common/_buttons.scss:

...
.crm-hover-button,
... {
  @extend %btn;
}

The %btn changes the font to OpenSans while it should be kept as FontAwesome but only for icons, so:

.crm-hover-button.crm-i {
  font-family: $font-family-fontawesome !important;
  // !important is needed because %btn contains !important too
}

is a safe way to keep the font correct and do not produce regressions.

Tests

This is an extremely minor change, so only manual tests were performed to save time.

[monishdeb]

Tested working fine:

[monishdeb]

Tested working fine. Based on two approval I am merging this PR