S3 Cache not working with IRSA in EKS 1.18
## Summary
S3 Cache not working for Gitlab Runner in EKS 1.18 with IRSA. This seems to happen since upgrading eks from 1.17 to 1.18
## Steps to reproduce
<!--
What do you need to do to reproduce the bug? Please include job definitions or git repository structure if relevant
-->
<details>
<summary> .gitlab-ci.yml </summary>
```yml
image: registry.gitlab.com/gitlab-org/terraform-images/stable:latest
variables:
TF_ROOT: ${CI_PROJECT_DIR}/${SERVICE}
cache:
key: c11h-terraform-${TEAM}-${SERVICE}
paths:
- ${TF_ROOT}/.terraform
```
</details>
## Actual behavior
<!--
What actually happens
-->
## Expected behavior
<!--
What you should see instead
-->
## Relevant logs and/or screenshots
```gitlab-1-ops-gitlab-runner-8494b66d66-7pznk gitlab-1-ops-gitlab-runner ERROR: error while generating S3 pre-signed URL error=Post sts.eu-central-1.amazonaws.com?Action=AssumeRoleWithWebIdentity&RoleArn=arn%3Aaws%3Aiam%3A%3A026861505133%3Arole%2Firsa-gitlab-1-ops-manager&RoleSessionName=1603453288209630053&Version=2011-06-15&WebIdentityToken=eyJhbGciOiJSUzI1NiIsImtpZCI6IjhlMWJiNzBkY2NlMGNlZjJjYmUzYmJlYTMyNjZkMDQ3MWUzOTc3ZTgifQ.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.VuWQipMrgopZVZs15ZZY8oKGt4h0bYmW3kb5Fja9PP3Gi9jYrrEGVenNUfgYwnHo9rhxZ4ARrOFq64PFmaPEgNLtvyabCKywGOpuebOi416knHuM0FagUIwulollZYCPXw7b5BXL5Pv3AH493cIApqAq0-PI1LpynjioIkP29zXdNIost4XQHTC5q_oQXr7jRAMn54Zj1DxTlwqyT5AjZS7_H8kCQHzPh2RmkjQu3-VLlyIGodzYqQrtKPJWQIywLgv4znTOcX1zG-XyijcQX2cptUPWNSzmuBQONP2YpcsnA-u0pyd5Nbk8dgJnzKiUhiEh58nkhFyi8CbY3bTwdA: unsupported protocol scheme ""```
<details>
<summary> job log </summary>
```sh
Add the job log
```
</details>
## Environment description
GitLab Enterprise Edition 13.5.1-ee
```
git@gitlab-server-webservice-5bdc88b9b-sbc9b:/$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 9 (stretch)"
NAME="Debian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
VERSION_CODENAME=stretch
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
```
<!--
Please add the contents of `config.toml` inside of the code blocks (```)
below, remember to remove any secret tokens!
-->
<details>
<summary> config.toml contents </summary>
```listen_address = ":9252"
concurrent = 50
check_interval = 5
log_level = "warn"
[session_server]
session_timeout = 1800
[[runners]]
name = "gitlab-1-ops-gitlab-runner-8494b66d66-7pznk"
output_limit = 8192
request_concurrency = 1
url = "https://ourgit.com/"
token = "token"
executor = "kubernetes"
[runners.custom_build_dir]
[runners.cache]
Type = "s3"
Path = "ops"
Shared = true
[runners.cache.s3]
ServerAddress = "s3.amazonaws.com"
BucketName = "secretbucket"
BucketLocation = "eu-central-1"
[runners.cache.gcs]
[runners.cache.azure]
[runners.kubernetes]
host = ""
bearer_token_overwrite_allowed = false
image = "docker:stable"
namespace = "ops-k8srunner"
namespace_overwrite_allowed = ""
privileged = true
cpu_limit = "6"
cpu_limit_overwrite_max_allowed = "16"
cpu_request = "128m"
cpu_request_overwrite_max_allowed = "16"
memory_limit = "28Gi"
memory_limit_overwrite_max_allowed = "48Gi"
memory_request = "512Mi"
memory_request_overwrite_max_allowed = "48Gi"
service_cpu_limit = "4"
service_cpu_request = "128m"
service_memory_limit = "10000Mi"
service_memory_request = "512Mi"
helper_cpu_limit = "4"
helper_cpu_request = "128m"
helper_memory_limit = "10000Mi"
helper_memory_request = "512Mi"
poll_timeout = 1200
service_account = "gitlab-1-ops-executor"
service_account_overwrite_allowed = ""
pod_annotations_overwrite_allowed = ""
[runners.kubernetes.node_selector]
autoscaling-node = "true"
[runners.kubernetes.node_tolerations]
"autoscaling-node=false" = "NoExecute"
[runners.kubernetes.affinity]
[runners.kubernetes.pod_security_context]
[runners.kubernetes.volumes]
```
</details>
### Used GitLab Runner version
```
Version: 13.5.0
Git revision: ece86343
Git branch: 13-5-stable
GO version: go1.13.8
Built: 2020-10-20T12:05:22+0000
OS/Arch: linux/amd64
```
## Possible fixes
https://github.com/gitlabhq/gitlab-runner/blob/master/cache/s3/minio.go
issue