Update diagnosticPath1.md

Author: gitvag7

undergraduate/diagnosticPath1.md

@@ -23,6 +23,6 @@ tooltips: true
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- <h2 class="mb-4"> Diagnostic: Which course is the best place to start?  </h2>
+ <h3 class="mb-4"> Which course is the best place to start?  </h3>
  <p>Simply pick the course that is most interesting to you and sign up!</p>