[MM-63556] mmctl: Add compliance export download cmd (#30576)

* add mmctl compliance export download command and tests

- Introduced `ComplianceExportDownloadCmd` to facilitate downloading compliance export files.
- Implemented the `DownloadComplianceExport` method in the Client interface for handling file downloads.
- Added unit tests for the download command, covering successful downloads, error handling for non-existent jobs, and retries on failure.
- Included end-to-end tests to validate the command's functionality.
- Updated documentation to include usage examples and options for the new command.

* don't know why this was left out

* PR comments

* adjust test for new retry logic

* refactored download fn for compliance_export and export

* fix test due to fixed logic

* docs

server/cmd/mmctl/docs/mmctl_compliance-export.rst

@@ -38,6 +38,7 @@ SEE ALSO
 
 * `mmctl <mmctl.rst>`_ 	 - Remote client for the Open Source, self-hosted Slack-alternative
 * `mmctl compliance-export cancel <mmctl_compliance-export_cancel.rst>`_ 	 - Cancel compliance export job
+* `mmctl compliance-export download <mmctl_compliance-export_download.rst>`_ 	 - Download compliance export file
 * `mmctl compliance-export list <mmctl_compliance-export_list.rst>`_ 	 - List compliance export jobs, sorted by creation date descending (newest first)
 * `mmctl compliance-export show <mmctl_compliance-export_show.rst>`_ 	 - Show compliance export job
 

server/cmd/mmctl/docs/mmctl_compliance-export_download.rst

@@ -0,0 +1,52 @@
+.. _mmctl_compliance-export_download:
+
+mmctl compliance-export download
+--------------------------------
+
+Download compliance export file
+
+Synopsis
+~~~~~~~~
+
+
+Download compliance export file
+
+::
+
+  mmctl compliance-export download [complianceExportJobID] [output filepath (optional)] [flags]
+
+Examples
+~~~~~~~~
+
+::
+
+    compliance_export download o98rj3ur83dp5dppfyk5yk6osy
+
+Options
+~~~~~~~
+
+::
+
+  -h, --help              help for download
+      --num-retries int   Number of retries if the download fails (default 5)
+
+Options inherited from parent commands
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+      --config string                path to the configuration file (default "$XDG_CONFIG_HOME/mmctl/config")
+      --disable-pager                disables paged output
+      --insecure-sha1-intermediate   allows to use insecure TLS protocols, such as SHA-1
+      --insecure-tls-version         allows to use TLS versions 1.0 and 1.1
+      --json                         the output format will be in json format
+      --local                        allows communicating with the server through a unix socket
+      --quiet                        prevent mmctl to generate output for the commands
+      --strict                       will only run commands if the mmctl version matches the server one
+      --suppress-warnings            disables printing warning messages
+
+SEE ALSO
+~~~~~~~~
+
+* `mmctl compliance-export <mmctl_compliance-export.rst>`_ 	 - Management of compliance exports
+