DRIVERS-698 copied below:

This ticket groups multiple small changes made to the Client Side Encryption spec. Each individual SPEC ticket has more detailed information and links to the associated PR, but the following summarizes necessary changes

SPEC-1431 Add API for specifying a custom endpoint with AWS masterkey provider

• Update bindings to libmongocrypt to call mongocrypt_ctx_setopt_masterkey_aws_endpoint with the value of "endpoint" is passed DataKeyOpts.masterKey
• Update libmongocrypt to latest version.
• Implement prose test under the section Custom Endpoint Test.

SPEC-1449 createDataKey returns UUID

• Update the return type (if necessary) of createDataKey to be a BSON binary

SPEC-1469 silence mongocryptd by default

• Spawned mongocryptd should redirect stdout and stderr to /dev/null

SPEC-1466 test that fetching keys uses readConcern=majority

• Resync the FLE JSON spec tests

SPEC-1452 test that created data keys insert with majority writeConcern

• Update the prose test of Data key and double encryption to check command started events

SPEC-1397 limit 2MiB limit to bulk writes

• Check that bulk write batch splitting logic matches the section "Size limits for Write Commands"
• Update the prose test under the section BSON size limits and batch splitting.