[backport] #16716 fix _utilities.less font-size issue

[Karlasa]

Description

backport of PR #16716

Fixed Issues (if relevant)

Manual testing scenarios

look product toolbar pager number css
should be:

.pages .item {
font-size: 1.2rem;
...
}

is:
.pages .item {
font-size: 1.2rem;
font-size: 12px;
...
}

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @Karlasa. Thank you for your contribution.
We will aim to release these changes as part of 2.1.15.
Please check the release notes for final confirmation.