fix(openshift): handle missing TektonConfig during TLS resolution

[wangyusheng1985]

Changes

Make OpenShift component TLS configuration resolution safe when the optional TektonConfig object is absent. A Kubernetes API NotFound result or a nil lister object now produces no TLS environment variables and no retry-triggering error; other lister errors continue to propagate.

Submitter Checklist

• Includes focused regression tests
• Updated nearby behavior documentation
• No API or dependency changes

Validation

• gofmt -d pkg/reconciler/openshift/common/tlsprofile.go pkg/reconciler/openshift/common/tlsprofile_test.go && git diff --check
• go test ./pkg/reconciler/openshift/common
• go test -race ./pkg/reconciler/openshift/common

NONE

Validation observed for this change:

• gofmt -d pkg/reconciler/openshift/common/tlsprofile.go pkg/reconciler/openshift/common/tlsprofile_test.go && git diff --check
• go test ./pkg/reconciler/openshift/common
• go test -race ./pkg/reconciler/openshift/common

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[linux-foundation-easycla]

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• ✅ login: wangyusheng1985 / name: wangyusheng1985 (7dc79d7)

[jkhelil]

Hi @wangyusheng1985, thank you for your first contribution we really appreciate it!
Could you please explain how you came across this issue and raised this PR? Did you encounter this bug in a real-world scenario while running Tekton Operator?
Since this function is specifically related to OpenShift, could you also provide some evidence or steps showing that the change resolves the issue?