Add CODEOWNERS file to repo (#7208)

Author: nateprewitt

.github/CODEOWNERS

@@ -0,0 +1,8 @@
+# Restrict all files related to deploying to
+# require lead maintainer approval.
+
+.github/workflows/            @nateprewitt @sigmavirus24
+.github/CODEOWNERS            @nateprewitt @sigmavirus24
+src/requests/__version__.py   @nateprewitt @sigmavirus24
+HISTORY.md                    @nateprewitt @sigmavirus24
+pyproject.toml                @nateprewitt @sigmavirus24