Updating sretrchr/testify version

This PR updates sretchr/testify to the latest version. The main reason for this is because of a vulnerability in gopkg.in/yaml.v3 which was fixed v3.0.1.
go/pkg/mod/github.com/go-task/slim-sprig@v0.0.0-20230315185526-52ccab3ef572/go.mod (gomod)
==========================================================================================
Total: 1 (HIGH: 1, CRITICAL: 0)

┌──────────────────┬────────────────┬──────────┬───────────────────────────────────┬───────────────────────────────────┬─────────────────────────────────────────────────────────┐
│     Library      │ Vulnerability  │ Severity │         Installed Version         │           Fixed Version           │                          Title                          │
├──────────────────┼────────────────┼──────────┼───────────────────────────────────┼───────────────────────────────────┼─────────────────────────────────────────────────────────┤
│ gopkg.in/yaml.v3 │ CVE-2022-28948 │ HIGH     │ 3.0.0-2020031[310](https://github.com/zuvaai/aitk-mlc/actions/runs/4535412124/jobs/7990827947?pr=78#step:11:317)2051-9f266ea9e77c │ 3.0.0-20220521103104-8f96da9f5d5e │ golang-gopkg-yaml: crash when attempting to deserialize │
│                  │                │          │                                   │                                   │ invalid input                                           │
│                  │                │          │                                   │                                   │ https://avd.aquasec.com/nvd/cve-2022-28948              │
└──────────────────┴────────────────┴──────────┴───────────────────────────────────┴───────────────────────────────────┴─────────────────────────────────────────────────────────┘
go-task / slim-sprig

Updating sretrchr/testify version #12
