chore: capitalize project.urls (#1220)

They appear exactly as-is on https://pypi.org/project/pystac/.

pyproject.toml

@@ -67,11 +67,11 @@ urllib3 = ["urllib3>=1.26"]
 validation = ["jsonschema~=4.18"]
 
 [project.urls]
-homepage = "https://github.com/stac-utils/pystac"
-documentation = "https://pystac.readthedocs.io"
-repository = "https://github.com/stac-utils/pystac.git"
-changelog = "https://github.com/stac-utils/pystac/blob/main/CHANGELOG.md"
-discussions = "https://github.com/radiantearth/stac-spec/discussions/categories/stac-software"
+Homepage = "https://github.com/stac-utils/pystac"
+Documentation = "https://pystac.readthedocs.io"
+Repository = "https://github.com/stac-utils/pystac.git"
+Changelog = "https://github.com/stac-utils/pystac/blob/main/CHANGELOG.md"
+Discussions = "https://github.com/radiantearth/stac-spec/discussions/categories/stac-software"
 
 [tool.setuptools.packages.find]
 include = ["pystac*"]
@@ -85,9 +85,7 @@ line-length = 88
 select = ["E", "F", "I"]
 
 [tool.pytest.ini_options]
-filterwarnings = [
-    "error",
-]
+filterwarnings = ["error"]
 
 [build-system]
 requires = ["setuptools>=61.0"]