Pin linting tools to specific versions

Pinning runs the risk of fossilization, but it's better than chasing
down recently added ruff warnings in the middle of trying to write and
test some code.

Author: paravoid

pyproject.toml

@@ -48,15 +48,15 @@ optional-dependencies.tests = [
 ]
 optional-dependencies.type = [
     "ircstream[tests]",
-    "mypy",
+    "mypy==1.1.1",
     "types-PyYAML",
 ]
 optional-dependencies.lint = [
     "ircstream[tests]",
-    "validate-pyproject[all]",
-    "ruff",
-    "black",
-    "pylint",
+    "validate-pyproject[all]==0.12.2",
+    "ruff==0.0.260",
+    "black==23.3.0",
+    "pylint==2.17.1",
 ]
 optional-dependencies.dev = [
     "ircstream[tests]",