Add a space to homepage heading h1

We recently swapped the punctuation in the new visually hidden text in the homepage heading from a colon to a dash, but didn't include a space in front of the dash. This wasn't obvious visually or when tested with screen readers since the visually hidden text inserts a space chacter before it. However if the user turns off their stylesheets, there wouldn't be a space character before the dash.

app/views/homepage/_homepage_header.html.erb

@@ -8,9 +8,9 @@
       <h1 class="homepage-header__title" data-ga4-scroll-marker>
         <%# The indentation of the spans below reflects the copy. Ticket to investigate a programmatic solution: https://trello.com/c/kroI3kLZ/684-stop-extra-whitespace-being-added-inside-homepage-h1
          %>
-        <span class="govuk-!-margin-bottom-2 govuk-!-display-block"><%=t('homepage.index.intro_title.short_text')%></span><span class="govuk-visually-hidden">- </span>
-        <span class="homepage-header__intro homepage-inverse-header__intro--bold">
-        <%= t('homepage.index.intro_html') %></span>
+        <span class="govuk-!-margin-bottom-2 govuk-!-display-block"><%=t('homepage.index.intro_title.short_text')%></span>
+        <span class="govuk-visually-hidden">-</span>
+        <span class="homepage-header__intro homepage-inverse-header__intro--bold"><%= t('homepage.index.intro_html') %></span>
       </h1>
     </div>
     <div class="govuk-grid-row">