Unified naming for span ops

[antonpirker]

Having a unified naming for span ops helps the performance team to discover performance issues.
The ops in the tests are all hard coded, so the tests show if someone trying to change ops string.

A list of all available span ops can be found in the develop docs:
https://develop.sentry.dev/sdk/performance/span-operations/

Fixes #1643

[sl0thentr0py]

span op changes don't break anything but transaction op changes are breaking in terms of existing dashboards.
How do we want to push this out - major or minor with clear changelog entry?

[sl0thentr0py]

also is the new consistent span ops table in notion or on develop already? If develop, can you please add the link to the PR description?

[antonpirker]

Added link to develop doc to PR description.

[sl0thentr0py]

changes look ok, pls don't merge till we decide on roll-out

[antonpirker]

Note to self: document in the readme all the changes to span ops for everyone that has dashboards it could be breaking.

[antonpirker]

Maybe we can find out how many dashboards would be affected with this change.

Possible ways to go:
a) document all changes in changelog in an easy understandable way
b) show a message in the sentry.io product if the user has the new python sdk installed and has dashboard to tell her that she needs to update the dashboards.
c) .. ? ..

[antonpirker]

The definite guide of changed span/transaction ops:

asgi.server -> http.server
aws.request -> http.client
aws.request.stream -> http.client.stream
celery.submit -> queue.submit.celery
celery.task -> queue.task.celery
django.middleware -> middleware.django
django.signals -> event.django
django.template.render -> template.render
django.view -> view.render
http -> http.client
redis -> db.redis
rq.task -> queue.task.rq
serverless.function -> function.aws
serverless.function -> function.gcp
starlette.middleware -> middleware.starlette

[antonpirker]

Made a draft again so we do not accidentally merge it.

Also related to this one #1665