Fix GetK8sVersion for all the hosted providers

[valaparthvi]

What does this PR do?

1. Simplify GetK8sVersion for all the hosted providers to call list single variants of each minor version and return a version based on forUpgrade parameter.
2. Rename AKS ListSingleVariantAKSAvailableVersions to ListSingleVariantAKSAllVersions, also modify it to return the versions in descending order 1.28.3, 1.28.0, etc, and modify the tests using this function with required changes.

Which issue(s) this PR fixes (optional, in fixes #(, fixes #, ...) format, will close the issue(s) when PR gets merged):

Fixes #147

Checklist:

• [ ] Squashed commits into logical changes
• [ ] Documentation
• [x] GitHub Actions (if applicable) - GKE P0/Support Matrix :green_circle: (import k8s upgrade is re-run), GKE P0 Import re-run :green_circle: EKS P0/Support Matrix :green_circle: , AKS P0/Support Matrix :green_circle: (Failure with 1.27.16 is also reproducible manually and looks like a temporary failure)
  1. GKE P1 on 2.9-head uses 1.30.3-gke.1969000 - https://github.com/rancher/hosted-providers-e2e/actions/runs/10575523066/job/29299429366
  2. GKE P0 on 2.8-head uses 1.27.16-gke.1234000 (upgrade=true), and 1.28.13-gke.1006000 (upgrade=false) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10575520397/job/29299407442
  3. GKE Sync on 2.8-head - https://github.com/rancher/hosted-providers-e2e/actions/runs/10580174818
  4. AKS P1 on 2.9-head uses 1.30.3 - https://github.com/rancher/hosted-providers-e2e/actions/runs/10575516457/job/29299399455
  5. AKS P0 on 2.8-head uses 1.27.16 (upgrade=true), and 1.28.12 (upgrade=false) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10575511076/job/29299401402
  6. EKS P0 on 2.8-head uses 1.27 (ugprade=true), and 1.28 (upgrade=false) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10575527300/job/29301589326
  7. EKS P1 on 2.9-head - https://github.com/rancher/hosted-providers-e2e/actions/runs/10578087657
  8. EKS Sync on 2.8-head - https://github.com/rancher/hosted-providers-e2e/actions/runs/10580193647

Special notes for your reviewer:

[cpinjani]

Changes looks fine, for 2.9 please also run P0, SupportMatrix

[valaparthvi]

Changes looks fine, for 2.9 please also run P0, SupportMatrix

1. GKE P0/Support Matrix 🟢 (import k8s upgrade is re-run) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593165181/job/29354275476
2. GKE P0 Import re-run :green_circle: - https://github.com/rancher/hosted-providers-e2e/actions/runs/10597550011
3. EKS P0/Support Matrix 🟢 - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593162397/job/29354269851
4. AKS P0/Support Matrix 🟢 (Failure with 1.27.16 is also reproducible manually and looks like a temporary failure) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593159634/job/29354269902

[cpinjani]

Changes looks fine, for 2.9 please also run P0, SupportMatrix

1. GKE P0/Support Matrix 🟢 (import k8s upgrade is re-run) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593165181/job/29354275476
2. GKE P0 Import re-run 🟢 - https://github.com/rancher/hosted-providers-e2e/actions/runs/10597550011
3. EKS P0/Support Matrix 🟢 - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593162397/job/29354269851
4. AKS P0/Support Matrix 🟢 (Failure with 1.27.16 is also reproducible manually and looks like a temporary failure) - https://github.com/rancher/hosted-providers-e2e/actions/runs/10593159634/job/29354269902

JFYI, auto-aks-hp-ci-gcqfz is on version 1.27.16 which is not supported in this region

[valaparthvi]

JFYI, auto-aks-hp-ci-gcqfz is on version 1.27.16 which is not supported in this region

I was able to reproduce it manually on Rancher and Azure console. Even though 1.27.16 is visible on Azure console and rancher, I was not able to create the cluster.