Fix YamlRestTestPluginFuncTest on Windows (elastic#77063)

* Fix YamlRestTestPluginFuncTest on Windows

- need to normalize output before comparison
- should fix elastic#77060

* Minor cleanup after review

build-tools/src/integTest/groovy/org/elasticsearch/gradle/test/YamlRestTestPluginFuncTest.groovy

@@ -24,16 +24,14 @@ class YamlRestTestPluginFuncTest extends AbstractGradleFuncTest {
 
         when:
         def result = gradleRunner("dependencies").build()
-
+        def output = normalized(result.output)
         then:
-        result.output.contains("""
+        output.contains("""
 restTestSpecs
-\\--- org.elasticsearch:rest-api-spec:${VersionProperties.elasticsearch} FAILED
-""")
-        result.output.contains("""
+/--- org.elasticsearch:rest-api-spec:${VersionProperties.elasticsearch} FAILED""")
+        output.contains(normalized("""
 yamlRestTestImplementation - Implementation only dependencies for source set 'yaml rest test'. (n)
-\\--- org.elasticsearch.test:framework:8.0.0-SNAPSHOT (n)
-""")
+/--- org.elasticsearch.test:framework:${VersionProperties.elasticsearch} (n)"""))
     }
 
     def "yamlRestTest does nothing when there are no tests"() {