fix: Consider the existence of Istio when applying and deleting resources for Log Gateway

[shorim]

Description

Changes proposed in this pull request (what was done and why):

• When initializing otelcollector.GatewayApplyOptions for Log Gateway:
  • Pass the missing IstioEnabled and IstioExcludePorts fields
  • Pass the missing AllowedPorts field (for NetworkPolicy)
• Add istio sidecar injection for Log Gateway
• Adjust gatewayApplierDeleter.DeleteResources in Log Gateway to use istioStatusChecker

Changes refer to particular issues, PRs or documents:

Traceability

• The PR is linked to a GitHub issue.
• The follow-up issues (if any) are linked in the Related Issues section.
• If the change is user-facing, the documentation has been adjusted.
• If a CRD is changed, the corresponding Busola ConfigMap has been adjusted.
• The feature is unit-tested.
• The feature is e2e-tested.