[stubsabot] Bump stripe to 6.3.*

Release: https://pypi.org/pypi/stripe/6.3.0
Homepage: https://github.com/stripe/stripe-python
Repository: https://github.com/stripe/stripe-python
Changelog: https://github.com/stripe/stripe-python/blob/master/CHANGELOG.md

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Author: stubsabot

stubs/stripe/METADATA.toml

@@ -1,4 +1,4 @@
-version = "3.5.*"
+version = "6.3.*"
 upstream_repository = "https://github.com/stripe/stripe-python"
 partial_stub = true