Update buttons copy

Author: nienn

readthedocs-theme/templates/readthedocs/product.html

@@ -91,7 +91,7 @@ <h3 class="ui header inverted">Write with reStructuredText or Markdown</h3>
 
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-            <a href="https://docs.readthedocs.io/en/stable/guides/authors.html" class="ui button green fluid">Using RTD as a technical writer</a>
+            <a href="https://docs.readthedocs.io/en/stable/guides/authors.html" class="ui button green fluid">Guides for documentation authors</a>
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@@ -129,7 +129,7 @@ <h3 class="ui header inverted">Easy documentation deployment for technical teams
 
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-            <a href="https://docs.readthedocs.io/en/stable/guides/administrators.html" class="ui button green fluid">How RTD works for teams</a>
+            <a href="https://docs.readthedocs.io/en/stable/guides/administrators.html" class="ui button green fluid">Guides for project administrators</a>
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