dev: Upgrade stripe to v6 (#91270)

This PR aims to upgrade our stripe version from 5.5 -> 6.7

One interesting thing with this version is that now stripe pins the API
to the latest version with each new version of the python SDK that gets
released. We can "opt-out" of this by explicitly setting the API version
to be whatever we want, allowing us to upgrade the python SDK
independently of the stripe API. Which I _think_ will give us better
typing on the SDK when we accurately type the code. And auto completion,
etc.


[Notion](https://www.notion.so/sentry/Upgrading-Stripe-from-v3-to-latest-1c88b10e4b5d80adbf87f574c2929d27)

[Change
log](https://github.com/stripe/stripe-python/blob/v6.7.0/CHANGELOG.md)

Our API version is pinned here:
https://github.com/getsentry/getsentry/blob/084007241f7138359786fa0efa23dbf372be59f3/getsentry/settings.py#L29-L30

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Author: ajay-sentry

requirements-dev-frozen.txt

@@ -203,7 +203,7 @@ sortedcontainers==2.4.0
 soupsieve==2.3.2.post1
 sqlparse==0.5.0
 statsd==3.3.0
-stripe==5.5.0
+stripe==6.7.0
 structlog==22.1.0
 supervisor==4.2.5
 symbolic==12.14.1

requirements-frozen.txt

@@ -140,7 +140,7 @@ snuba-sdk==3.0.43
 soupsieve==2.3.2.post1
 sqlparse==0.5.0
 statsd==3.3.0
-stripe==5.5.0
+stripe==6.7.0
 structlog==22.1.0
 symbolic==12.14.1
 tiktoken==0.8.0

requirements-getsentry.txt

@@ -11,4 +11,4 @@ iso3166
 pycountry==17.5.14
 pyvat==1.3.15
 reportlab==4.4.0
-stripe==5.5.0
+stripe==6.7.0