This reverts commit f55cc6ab.

This reverts commit 237bcf8c.

* Sync download-mongodb.sh with drivers-evergreen-tools 8159c42f

* Update zSeries RHEL server versions being tested

* fix: _mongoc_get_cpu_count on android: get_nprocs is not available on Android below API level 23.
* Always use sysconf for Linux

Co-authored-by: ii14 <ii14@users.noreply.github.com>
Co-authored-by: vector-of-bool <vectorofbool@gmail.com>

* An API to get the crypt_shared version used for encryption

* Test that we bypassSpawn when using crypt_shared

* Fix: Don't spawn mongocryptd if we successfully loaded a crypt_shared

* Enforce strict C99 conformance for debug-compile-aws
* Fix C99 standard conformance detection in link-sample-program scripts
* Add BSON_ALIGNOF
* Redefine BSON_ALIGN_OF_PTR in terms of BSON_ALIGNOF
* Add bson_aligned_alloc and bson_aligned_alloc0
* Add BSON_ALIGNED_ALLOC macro to avoid type repetition
* Add mongoc_array_aligned_init
* Fix alignment of allocated objects
* Add documentation for pool_node layout
* Add -fno-sanitize-recover=alignment to debug-compile-ubsan
* Add debug-compile-ubsan-with-extra-alignment

Co-authored-by: Kevin Albertson <kevin.albertson@10gen.com>

Co-authored-by: ii14 <ii14@users.noreply.github.com>

* Sync CSE unified test files with 10b4a41f

* Use a Python virtual environment with upgraded boto3.

* Use separate client in shell auth.

* remove duplicate errexit

Syncs to mongodb/specifications commit 8d897ad01f8c600ddaef139740d5b68fd2950c0e

* Update future-functions generator

* Ensure collections are serialized in block style

* CDRIVER-4136 Use -std=c99 by default for all compilation on Evergreen

* Fix compatiblity issues with glibc versions 2.19 and earlier

* Remove debug-compile-c99 task from Evergreen

* Format source files

* Add BSON_UNUSED macro

* Address -Wunused-parameter warnings

* Use BSON_UNUSED instead of asserting with -Wtype-limits warning

* Allow a null URI for obtaining AWS credentials
* Implement on-demand credential loading for the AWS KMS provider
* New error handling since we always use NEEDS_CREDENTIALS

* Exclude bundled zlib from scan-build analysis