CORE-165: even more passthroughs

[davidangb]

Removes all calls to passthrough and replaces them with more generic streamingPassthrough calls. Removes the passthrough directive itself.

✅ passed unit tests

✅ passed swat tests

✅ manually tested while running locally:

1. used swagger-ui to check most of the APIs affected by this PR

✅ manually tested in a BEE:

1. create and share billing project
2. create workspace
3. import WDL from Dockstore to workspace
4. launch and complete a Cromwell submission

---

Have you read CONTRIBUTING.md lately? If not, do that first.

I, the developer opening this PR, do solemnly pinky swear that:

• I've followed the instructions if I've made any changes to the API, especially if they're breaking changes
• I've updated the FISMA documentation if I've made any security-related changes, including auth, encryption, or auditing

In all cases:

• Get two thumbsworth of review and PO signoff if necessary
• Verify all tests go green
• Squash and merge. Make sure your branch deletes; GitHub should do this for you.
• Test this change deployed correctly and works on dev environment after deployment