Fix Dependabot alerts: bump black and pytest (#32)

* Bump black to 26.3.1 and pytest to 9.0.3 to fix Dependabot alerts

Resolves GHSA-3936-cmfr-pm3m (black arbitrary file writes, high) and
GHSA-6w46-j5rx-g56g (pytest tmpdir handling, medium). black 26.x requires
Python >=3.10, so requires-python is bumped accordingly (CI already runs 3.13).

* Tidy pyproject.toml: fix author name and inline dev deps

* Bump Python to 3.14

- requires-python >=3.14
- black target-version py314
- CI runs on Python 3.14

Author: jtprogru

.github/workflows/testing.yml

@@ -18,8 +18,8 @@ jobs:
       with:
         enable-cache: true
 
-    - name: Set up Python 3.13
-      run: uv python install 3.13
+    - name: Set up Python 3.14
+      run: uv python install 3.14
 
     - name: Install dependencies
       run: uv sync

pyproject.toml

@@ -3,25 +3,20 @@ name = "interview-task"
 version = "0.1.0"
 description = "Задачки с собеседований, LeetCode, CodeWars (решаю их на Python)"
 readme = "README.md"
-requires-python = ">=3.9"
+requires-python = ">=3.14"
 license = { text = "MIT" }
-authors = [{ name = "Michael Savin", email = "jtprogru@gmail.com" }]
+authors = [{ name = "Mikhail Savin", email = "jtprogru@gmail.com" }]
 dependencies = []
 
 [dependency-groups]
-dev = [
-    "black==25.1.0",
-    "flake8==7.1.2",
-    "isort==6.0.1",
-    "pytest==8.3.5",
-]
+dev = ["black==26.3.1", "flake8==7.1.2", "isort==6.0.1", "pytest==9.0.3"]
 
 [tool.uv]
 package = false
 
 [tool.black]
 line-length = 120
-target-version = ['py38', 'py39']
+target-version = ['py314']
 include = '\.pyi?$'
 
 [tool.isort]