Revert "Update langchain from 0.3.13 to 0.3.14"

This reverts commit a7ae2de.

Hold back this update as it seems to trigger recursion error in
combination with other dependencies from this update.

requirements-test-libraries.txt

@@ -217,7 +217,7 @@ z3c.rml==4.4.0
 freetype-py==2.5.1
 vaderSentiment==3.3.2
 # langchain depends on numpy<2.0.0, which does not have binary wheels for python 3.13.
-langchain==0.3.14; python_version >= '3.9' and python_version < '3.13'
+langchain==0.3.13; python_version >= '3.9' and python_version < '3.13'
 seedir==0.5.0
 cel-python==0.1.5
 # pygwalker depends on quickjs, which at the time of writing (v1.19.4) cannot be built under python 3.13.