Backport PR pandas-dev#27809: CI: remove pytest pins (pandas-dev#27819)

Author: meeseeksmachine

ci/deps/azure-36-locale.yaml

@@ -20,8 +20,8 @@ dependencies:
   - xlsxwriter=0.9.8
   - xlwt=1.2.0
   # universal
-  - pytest>=4.0.2,<5.0.0
-  - pytest-xdist
+  - pytest>=5.0.0
+  - pytest-xdist>=1.29.0
   - pytest-mock
   - pytest-azurepipelines
   - hypothesis>=3.58.0

ci/deps/travis-36-slow.yaml

@@ -25,8 +25,8 @@ dependencies:
   - xlsxwriter
   - xlwt
   # universal
-  - pytest>=4.0.2,<5.0.0
-  - pytest-xdist
+  - pytest>=5.0.0
+  - pytest-xdist>=1.29.0
   - pytest-mock
   - moto
   - hypothesis>=3.58.0