docs: add info about testing with different versions and the rosetta setup for Mac

test/readme.md

@@ -10,6 +10,8 @@ about the types of tests and how to run them.
   - [About the Tests](#about-the-tests)
     - [Spec Tests](#spec-tests)
   - [Running the Tests Locally](#running-the-tests-locally)
+    - [Testing Against Different Versions](#testing-against-different-versions)
+      - ["Bad CPU type in executable" error](#bad-cpu-type-in-executable-error)
     - [Testing With Authorization-Enabled](#testing-with-authorization-enabled)
     - [Testing Different MongoDB Topologies](#testing-different-mongodb-topologies)
     - [Running Individual Tests](#running-individual-tests)
@@ -118,6 +120,33 @@ The output will show how many tests passed, failed, and are pending. Tests that
 
 In the following subsections, we'll dig into the details of running the tests.
 
+### Testing Against Different Versions
+
+Sometimes you'll need to run tests against a specific version, such as "7.0", and to do that you can use the `VERSION` env var.
+
+```sh
+VERSION=7.0 TOPOLOGY='replica_set' bash .evergreen/run-orchestration.sh
+```
+
+Older versions of MongoDB may not have Mac binaries, so you may also need to specify a different architecture:
+
+```sh
+VERSION=4.2 ARCH=x86_64 TOPOLOGY='replica_set' bash .evergreen/run-orchestration.sh
+```
+
+#### "Bad CPU type in executable" error
+
+You may encounter this error if Rosetta isn't properly configured on your system.
+```txt
+OSError: [Errno 86] Bad CPU type in executable: '.../node-mongodb-native/drivers-evergreen-tools/mongodb/bin/mongod'
+```
+
+To fix it, simply run:
+
+```sh
+softwareupdate --install-rosetta
+```
+
 ### Testing With Authorization-Enabled
 
 By default, the integration tests run with auth-enabled and the mongo orchestration script will run with auth enabled when the `AUTH` variable is set to `auth`. Tests can be run locally without auth by setting the environment variable `AUTH` to the value of `noauth`.  This must be a two-step process of starting a server without auth-enabled and then running the tests without auth-enabled.
@@ -505,7 +534,7 @@ The following steps will walk you through how to run the tests for CSFLE.
 ```bash
 npm install mongodb-client-encryption
 ```
-> [!NOTE] 
+> [!NOTE]
 > If developing changes in `mongodb-client-encryption`, you can link it locally using `etc/tooling/fle.sh`.
 
 2. Load FLE credentials and download crypt_shared
@@ -517,8 +546,8 @@ source .evergreen/setup-fle.sh
 ```
 
 > [!NOTE]
-> By default, `setup-fle.sh` installs crypt_shared.  If you want to test with mongocryptd instead, set the RUN_WITH_MONGOCRYPTD environment variable before 
-> sourcing `setup-fle.sh`. 
+> By default, `setup-fle.sh` installs crypt_shared.  If you want to test with mongocryptd instead, set the RUN_WITH_MONGOCRYPTD environment variable before
+> sourcing `setup-fle.sh`.
 
 3. Run the functional tests:
 ```bash
@@ -546,7 +575,7 @@ All of this is handled in the csfle/azurekms and csfle/gcpkms folders in drivers
 
 #### Azure KMS
 
-1. Provision an Azure server.  You must set the `AZUREKMS_VMNAME_PREFIX` variable: 
+1. Provision an Azure server.  You must set the `AZUREKMS_VMNAME_PREFIX` variable:
 
 ```bash
 export AZUREKMS_VMNAME_PREFIX: "NODE_DRIVER"