fix(GlPagination): Fix extra space between span and icon

mentioned in commit 45178096

mentioned in merge request rpadovani/daintree!307 (merged)

mentioned in merge request gitlab!45705 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!2127 (merged)

mentioned in merge request status-page!130 (merged)

mentioned in merge request gitlab!45765 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!2128 (merged)

mentioned in merge request gitlab-docs!1270 (merged)