fix: allow to set K8s namespace via env var

[konstan]

Closes https://github.com/SixSq/tasklist/issues/3543

[Copilot]

Pull Request Overview

This PR refactors the Kubernetes namespace handling logic by moving namespace extraction from manifest files from the Kubernetes class to the K8sDriver class, making it private. The change relocates the namespace validation logic to be closer to where the manifest is actually applied.

• Moved namespace extraction logic from Kubernetes.start() to K8sDriver.apply_manifest_with_context()
• Made the get_all_namespaces_from_manifest method private by renaming it to _get_all_namespaces_from_manifest
• Simplified the namespace handling in the Kubernetes.start() method to use deployment UUID as default

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
nuvla/job_engine/connector/kubernetes.py	Removed namespace extraction logic and simplified to use deployment UUID as default namespace
nuvla/job_engine/connector/k8s_driver.py	Added namespace extraction and validation logic, made the helper method private

[github-actions]

Test Results

67 tests  ±0   67 ✅ ±0   1s ⏱️ ±0s
 1 suites ±0    0 💤 ±0 
 1 files   ±0    0 ❌ ±0 

Results for commit 4a438d5. ± Comparison against base commit b1442b8.

♻️ This comment has been updated with latest results.