test: remove fragile timeout test

The timeout test is environment-dependent and fragile because it relies
on external infrastructure being slow enough to trigger a timeout with a
1-second limit. This makes it unreliable in CI environments with varying
network speeds and API response times.

The readTimeoutSeconds parameter support remains in place as it's still
a useful configuration option for the Jenkins plugin.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: janisz

functionaltest-jenkins-plugin/src/test/groovy/ImageScanningTest.groovy

@@ -21,15 +21,6 @@ class ImageScanningTest extends BaseSpecification {
     protected static final String CENTRAL_URI = Config.roxEndpoint
     protected static final String QUAY_REPO = "quay.io/openshifttest/"
 
-    def "Test read timeout with minimal timeout should fail"() {
-        when:
-        BuildResult status = jenkins.createAndRunJob(
-                getJobConfig("nginx-alpine:latest", false, true, 1))
-
-        then:
-        assert status == FAILURE
-    }
-
     @Unroll
     def "image scanning test with toggle enforcement(#imageName, #policyName,  #enforcements, #endStatus)"() {
         given: