CI: pin markupsafe to avoid import error (pandas-dev#46054)

* CI: pin markupsafe to avoid import error

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Author: phofl

ci/deps/actions-38-minimum_versions.yaml

@@ -19,7 +19,7 @@ dependencies:
   - numpy=1.18.5
   - pytz=2020.1
 
-  # optional dependencies
+  # optional dependencies, markupsafe for jinja2
   - beautifulsoup4=4.8.2
   - blosc=1.20.1
   - bottleneck=1.3.1
@@ -29,6 +29,7 @@ dependencies:
   - gcsfs=0.6.0
   - jinja2=2.11
   - lxml=4.5.0
+  - markupsafe=2.0.1
   - matplotlib=3.3.2
   - numba=0.50.1
   - numexpr=2.7.1

pandas/compat/_optional.py

@@ -19,6 +19,7 @@
     "gcsfs": "0.6.0",
     "jinja2": "2.11",
     "lxml.etree": "4.5.0",
+    "markupsafe": "2.0.1",
     "matplotlib": "3.3.2",
     "numba": "0.50.1",
     "numexpr": "2.7.1",