[MISC] Fix Python 3.12 compatibility (#428)

This PR fixes Python 3.12 compatibility after the pathlib.Path family of
classes changed in order to tweak how they behave when they are are
extended via sub-classes.

#### References
- Python 3.12 [release
notes](https://docs.python.org/3/whatsnew/3.12.html#pathlib).

#### Additional changes
- Update `data-integrator` charm base to fix integration tests

Author: sinclert-canonical

.github/workflows/ci.yaml

@@ -39,7 +39,7 @@ jobs:
 
   unit-test:
     name: Unit test charm
-    runs-on: ubuntu-22.04  # TODO: use ubuntu-latest after fixing pathlib issue on python 3.12
+    runs-on: ubuntu-latest
     timeout-minutes: 20
     steps:
       - name: Checkout

src/rock.py

@@ -9,6 +9,7 @@
 import ops
 
 import container
+import utils
 
 if typing.TYPE_CHECKING:
     import relations.cos
@@ -22,10 +23,14 @@
 class _Path(container.Path):
     """Rock filesystem path"""
 
-    def __new__(cls, *args, container_: ops.Container):
-        path = super().__new__(cls, *args)
-        path._container = container_
-        return path
+    # TODO python3.10 min version: remove when min version >= 3.12
+    def __new__(cls, *args, **kwargs):
+        return super().__new__(cls, *args)
+
+    def __init__(self, *args, container_: ops.Container):
+        if utils.python_version_after_3_12:
+            super().__init__(*args)
+        self._container = container_
 
     def __truediv__(self, other):
         return type(self)(self, other, container_=self._container)

src/utils.py

@@ -5,6 +5,12 @@
 
 import secrets
 import string
+import sys
+
+python_version_after_3_12 = all((
+    sys.version_info[0] == 3,
+    sys.version_info[1] >= 12,
+))
 
 
 def generate_password() -> str: