add explanation about workshop recordings (#863)

Author: tobyhodges

index.md

@@ -262,6 +262,17 @@ special instructions.
   for their learners.
 </p>
 
+{% comment %}
+WORKSHOP RECORDINGS
+
+Modify or remove the block below if you plan to record the workshop.
+{% endcomment %}
+<p id="recordings">
+  <strong>Workshop Recordings:</strong>
+  Carpentries workshops are designed to be interactive rather than lecture-based, with lessons that build upon one another.
+  To foster a positive online learning environment, we strongly recommend that participants join in real time.
+  As a result, workshop recordings are not recommended and may not be available to learners.
+</p>
 {% comment %}
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