reduce dependencies

.ci_support/environment.yml

@@ -9,7 +9,7 @@ dependencies:
   - sphinx =2.4.4
   - pybtex
   - jupyter_sphinx
-  - jupyter-cache =0.4.2
+  - jupyter-cache =0.4.1
   - linkify-it-py =1.0.1
   - sphinxcontrib-bibtex
   - markdown-it-py
@@ -23,11 +23,11 @@ dependencies:
   - nbdime
   - soupsieve =2.2
   - sphinx-copybutton
-  - sphinx-book-theme =0.0.41
+  - sphinx-book-theme =0.0.40
   - sphinx-comments =0.0.3
   - sphinx-panels =0.5.2
-  - sphinx-thebe =0.0.8
-  - sphinx-togglebutton =0.2.3
+  - sphinx-thebe =0.0.7
+  - sphinx-togglebutton =0.2.2
   - sqlalchemy =1.3.23
   - uc-micro-py =1.0.1
   - pydata-sphinx-theme