Remove reference to development philosophy
# Contribution Guidelines
-Before opening any issues or proposing any pull requests, please do the
-following:
-
-1. Read our [Contributor's Guide](https://requests.readthedocs.io/en/latest/dev/contributing/).
-2. Understand our [development philosophy](https://requests.readthedocs.io/en/latest/dev/philosophy/).
+Before opening any issues or proposing any pull requests, please read
+our [Contributor's Guide](https://requests.readthedocs.io/en/latest/dev/contributing/).
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following additional notes.
