chore: lower flake8 dependency version for gym compatibility

Author: jelledouwe

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+
+updates:
+  - package-ecosystem: "pip"
+    directory: "/"
+    schedule:
+      interval: "daily"
+    commit-message:
+      # Prefix all commit messages with "npm"
+      prefix: "chore: "

pyproject.toml

@@ -10,13 +10,13 @@ documentation = "https://eagerx.readthedocs.io/en/master/"
 
 [tool.poetry.dependencies]
 python = "^3.6.2"
-eagerx = "^0.1.10"
+eagerx = "^0.1.13"
 
 [tool.poetry.dev-dependencies]
 black = "^22.1.0"
 pytest = "^7.0"
 pytest-cov = "^3.0.0"
-flake8 = "^4.0.1"
+flake8 = "^3.0"
 flake8-bugbear = "^22.3.23"
 
 [build-system]