add script to backup csv (#240)

# Summary
This pull request introduces a new script and corresponding Evergreen
tasks to backup digest-pinned images from a ClusterServiceVersion (CSV)
YAML file to Quay.io. The changes include adding a Python script to
perform the backup process, new Evergreen tasks to execute the script,
and a new build variant for these tasks.

### New Evergreen tasks and build variant:

*
[`.evergreen.yml`](diffhunk://#diff-9a7744843f307953832ec106e8d49be546037475db24ec6873e5fec6249c236dR608-R647):
Added three new tasks (`backup_csv_images_dry_run`,
`backup_csv_images_limit_3`, and `backup_csv_images_all`) to run the
backup script with different options, and created a new build variant
(`backup_csv_images`) to group these tasks under the "Backup CSV Images"
workflow.
[[1]](diffhunk://#diff-9a7744843f307953832ec106e8d49be546037475db24ec6873e5fec6249c236dR608-R647)
[[2]](diffhunk://#diff-9a7744843f307953832ec106e8d49be546037475db24ec6873e5fec6249c236dR1245-R1255)

### New Python script for image backup:

*
[`scripts/dev/release/backup_csv_images.py`](diffhunk://#diff-cd0fc9d64b8e8c03c901ad1ebcba9734985ab170613937b2b0e7dcb91b94037cR1-R370):
Added a comprehensive Python script to parse a CSV file, extract
digest-pinned images, and back them up to Quay.io using a new tag format
(`_openshift_<mck_version>`). The script supports dry-run mode, logging,
and limiting the number of images to back up.

## Proof of Work


https://parsley.mongodb.com/evergreen/mongodb_kubernetes_backup_csv_images_backup_csv_images_all_patch_5710105f0347aed651ce63e6b37f06051caa634a_686e4ee749d2610007d96aaa_25_07_09_11_13_48/0/task?bookmarks=0,11182&shareLine=3143
![Screenshot 2025-07-09 at 14 10
21](https://github.com/user-attachments/assets/82717ced-b4df-4b64-867d-d789cc662de8)

![Screenshot 2025-07-09 at 14 10
33](https://github.com/user-attachments/assets/7e34a30d-3439-4792-b1af-cfd9e713a2be)


## Checklist
- [x] Have you linked a jira ticket and/or is the ticket in the title?
- [x] Have you checked whether your jira ticket required DOCSP changes?
- [x] Have you checked for release_note changes?

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Author: nammn

.evergreen.yml

@@ -610,6 +610,46 @@ tasks:
           variant: prepare_openshift_bundles
           task: prepare_and_upload_openshift_bundles
 
+  - name: backup_csv_images_dry_run
+    commands:
+      - func: clone
+      - func: quay_login
+      - command: subprocess.exec
+        params:
+          working_dir: src/github.com/mongodb/mongodb-kubernetes
+          binary: python3
+          args:
+            - scripts/dev/release/backup_csv_images.py
+            - scripts/dev/release/1.2.0.clusterserviceversion.yaml
+            - --dry-run
+            - --verbose
+  - name: backup_csv_images_limit_3
+    commands:
+      - func: clone
+      - func: quay_login
+      - command: subprocess.exec
+        params:
+          working_dir: src/github.com/mongodb/mongodb-kubernetes
+          binary: python3
+          args:
+            - scripts/dev/release/backup_csv_images.py
+            - scripts/dev/release/1.2.0.clusterserviceversion.yaml
+            - --limit
+            - "3"
+            - --verbose
+  - name: backup_csv_images_all
+    commands:
+      - func: clone
+      - func: quay_login
+      - command: subprocess.exec
+        params:
+          working_dir: src/github.com/mongodb/mongodb-kubernetes
+          binary: python3
+          args:
+            - scripts/dev/release/backup_csv_images.py
+            - scripts/dev/release/1.2.0.clusterserviceversion.yaml
+            - --verbose
+
 task_groups:
   - name: unit_task_group
     max_hosts: -1
@@ -1207,6 +1247,17 @@ task_groups:
 
 buildvariants:
 
+  ## Backup CSV Images Variant
+  - name: backup_csv_images
+    display_name: "Backup CSV Images"
+    tags: [ "release_csv_backup" ]
+    run_on:
+      - ubuntu2204-small
+    tasks:
+      - name: backup_csv_images_dry_run
+      - name: backup_csv_images_limit_3
+      - name: backup_csv_images_all
+
   ## Unit tests + lint build variant
 
   - name: unit_tests