Fix ruff and mypy warnings

Fix deprecation warnings for `ruff` about invoking it as `ruff .`
(instead of `ruff check .` and about configuring linting settings
for it as `[tool.ruff]` in the `pyproject.toml` (instead of as
`[tool.ruff.lint]`.

Fix warning from `mypy` that enabling `Unpack` support is no longer
necessary.

These changes bring these tools in line with the expectations set
by running them on GitHub.

You may need to refresh your linting environment. Run `hatch prune`
to delete your existing Hatch environments.

pyproject.toml

@@ -94,16 +94,16 @@ dependencies = [
 ]
 
 [tool.hatch.envs.lint.scripts]
-typing = "mypy --enable-incomplete-feature=Unpack {args}"
+typing = "mypy {args}"
 style = [
-  "ruff {args:.}",
+  "ruff check {args:.}",
   "isort --check {args:.}",
   "black --check --diff {args:.}",
 ]
 fmt = [
   "isort {args:.}",
   "black {args:.}",
-  "ruff --fix {args:.}",
+  "ruff check --fix {args:.}",
 ]
 all = [
   "fmt",
@@ -114,6 +114,8 @@ all = [
 [tool.ruff]
 line-length = 90
 extend-exclude = ["src/scripts/agent.py"]
+
+[tool.ruff.lint]
 select = [
   "E", "W", "F",  # flake8 (pycodestyle and pyflakes)
   "N",    # pep8-naming

src/appsignal/opentelemetry.py

@@ -112,9 +112,9 @@ def start_opentelemetry(config: Config) -> None:
     # Configure OpenTelemetry request headers config
     request_headers = list_to_env_str(config.option("request_headers"))
     if request_headers:
-        os.environ[
-            "OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST"
-        ] = request_headers
+        os.environ["OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST"] = (
+            request_headers
+        )
 
     opentelemetry_port = config.option("opentelemetry_port")
     _start_opentelemetry_tracer(opentelemetry_port)