build: move e2e dependencies into e2e/go.mod

Several packages are only used while running the e2e suite. These
packages are less important to update, as the they can not influence the
final executable that is part of the Ceph-CSI container-image.

By moving these dependencies out of the main Ceph-CSI go.mod, it is
easier to identify if a reported CVE affects Ceph-CSI, or only the
testing (like most of the Kubernetes CVEs).

Signed-off-by: Niels de Vos <ndevos@ibm.com>

e2e/vendor/github.com/onsi/ginkgo/v2/CONTRIBUTING.md

@@ -0,0 +1,15 @@
+# Contributing to Ginkgo
+
+Your contributions to Ginkgo are essential for its long-term maintenance and improvement.
+
+- Please **open an issue first** - describe what problem you are trying to solve and give the community a forum for input and feedback ahead of investing time in writing code!
+- Ensure adequate test coverage:
+    - When adding to the Ginkgo library, add unit and/or integration tests (under the `integration` folder).
+    - When adding to the Ginkgo CLI, note that there are very few unit tests.  Please add an integration test.
+- Run `make` or:
+  - Install ginkgo locally via `go install ./...`
+  - Make sure all the tests succeed via `ginkgo -r -p`
+  - Vet your changes via `go vet ./...`
+- Update the documentation. Ginkgo uses `godoc` comments and documentation in `docs/index.md`.  You can run `bundle && bundle exec jekyll serve` in the `docs` directory to preview your changes.
+
+Thanks for supporting Ginkgo!