fix: Adjusted noisy trace filter to new istio reality

[a-thaler]

Description

It seems that the openTelemetry tracer of Istio changed its behaviour as the span name attribute does not contain the "ingress"|"egress" prefix anymore (#557). On that the noise filter was relying on. This PR fixes the noise filter by relying on the upstream_cluster field

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

• Switched the noise filter expression to rely on the istio upstream_cluster.name attribute for dtecting ingress or egress mode

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.