CI: Install uv and editables from PyPI: hatchling 1.24 requires them for testing

tests/unit/main.fmf

@@ -9,6 +9,7 @@ require:
   - python3-httpx
   - python3-packaging
   - python3-pathspec
+  - python3-pip
   - python3-platformdirs
   - python3-pytest
   - python3-pytest-mock

tests/unit/runtest.sh

@@ -1,5 +1,14 @@
 #!/bin/bash -eux
 
+# hatchling 1.24+ requires uv and editables for testing - they're not available
+# in our systems, hence PyPI installation
+# install the specific version of uv that has been released around the time
+# the tested hatchling's version was out
+# editables 0.5 has been released in July 2023, pinning it just to be sure it works
+# we don't rebase packages often in CentOS Stream, so version constraints
+# should be reasonably safe to be hardcoded
+pip install uv==0.1.35 editables==0.5
+
 # Get the version of our installed component
 VERSION=$(rpm -q --queryformat="%{VERSION}" python3-hatchling)