[2.7.6][BUG] Fleet v0.7.1-rc.1 is not in 2.7.6-head causing errors during docker install

[thaneunsoo]

Rancher Server Setup

• Rancher version: v2.7.6-head
• Installation option (Docker install/Helm Chart):
  • If Helm Chart, Kubernetes Cluster and version (RKE1, RKE2, k3s, EKS, etc): Docker Install
• Proxy/Cert Details:

Information about the Cluster

• Kubernetes version:
• Cluster Type (Local/Downstream):
  • If downstream, what type of cluster? (Custom/Imported or specify provider for Hosted/Infrastructure Provider):

User Information

• What is the role of the user logged in? (Admin/Cluster Owner/Cluster Member/Project Owner/Project Member/Custom)
  • If custom, define the set of permissions:

Describe the bug

When doing a docker install with the following command:

sudo docker run -d --restart=unless-stopped -p 80:80 -p 443:443 --privileged rancher/rancher:v2.7.6-head

the logs keep outputting

2023/07/28 15:14:26 [ERROR] Failed to find system chart fleet will try again in 5 seconds: no chart name found
2023/07/28 15:14:31 [ERROR] available chart version (102.1.0+up0.7.0) for fleet is less than the min version (102.1.1+up0.7.1-rc.1) 

To Reproduce

Install Rancher using docker command

sudo docker run -d --restart=unless-stopped -p 80:80 -p 443:443 --privileged rancher/rancher:v2.7.6-head

Result
the logs keep outputting

2023/07/28 15:14:26 [ERROR] Failed to find system chart fleet will try again in 5 seconds: no chart name found
2023/07/28 15:14:31 [ERROR] available chart version (102.1.0+up0.7.0) for fleet is less than the min version (102.1.1+up0.7.1-rc.1) 

Expected Result

The new updated chart version should be available #42237
It seems the branch is building using a charts repo that doesn't have that version

rancher/package/Dockerfile

Line 20 in 4a675a3

ARG CHART_DEFAULT_BRANCH=release-v2.7

[deniseschannon]

Once the build passes with this PR, this will be fixed and unblock all testing.

[thaneunsoo]

Test Environment:

Rancher version: v2.7.6-head 0113791
Rancher cluster type: single-node docker install
Docker version: 20.10

---

Testing:

With the Fleet chart version being reverted, the error in the logs are no longer reproducible and Rancher is successfully deployed using the following docker run

sudo docker run -d --restart=unless-stopped -p 80:80 -p 443:443 --privileged rancher/rancher:v2.7.6-head

[thardeck]

Fleet 0.7.1-rc.1 was added to the new charts branch rancher/charts#2816 (before it was only available in the dev.2.7 branch) and after #42263 is merged it should be available and working in Rancher 2.7.6.