test: remove AssertionGuiSpec as it duplicates existing org.apache.jmeter.junit.JMeterTest

junit.JMeterTest instantiates all detected Gui classes, create components,
and verify basic properties, so AssertionGuiSpec was not adding much

src/components/src/test/groovy/org/apache/jmeter/assertions/gui/AssertionGuiSpec.groovy

@@ -1,81 +0,0 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to you under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License.  You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.jmeter.assertions.gui
-
-import org.apache.jmeter.assertions.ResponseAssertion
-import org.apache.jmeter.junit.spock.JMeterSpec
-
-/**
- * Extending JMeterSpec is required to initialize resource bundle org.apache.jmeter.resource.messages
- */
-class AssertionGuiSpec extends JMeterSpec {
-
-    def sut = new AssertionGui()
-
-    private def langIsEnglish() {
-        return Locale.default.language.startsWith(Locale.ENGLISH.language)
-    }
-
-    def "init of new component does not throw an exception"() {
-        when:
-            sut.init()
-        then:
-            noExceptionThrown()
-    }
-
-    def "clearing GUI component fields does not throw an exception"() {
-        when:
-            sut.clearGui()
-        then:
-            noExceptionThrown()
-    }
-
-    def "Creation of ResponseAssertion sets name of element and enables it"() {
-        when:
-            def result = sut.createTestElement()
-        then:
-            (langIsEnglish() && result.name == "Response Assertion") ||
-                    (!langIsEnglish() && result.getName() != null && !result.getName().empty)
-            result.isEnabled()
-    }
-
-    def "Modification of ResponseAssertion by GUI has no unexpected behaviour"() {
-        given:
-            def element = new ResponseAssertion()
-            sut.clearGui()
-        when:
-            sut.modifyTestElement(element)
-        then:
-            (langIsEnglish() && element.name == "Response Assertion") ||
-                    (!langIsEnglish() && element.getName() != null && !element.getName().empty)
-            element.isTestFieldResponseData()
-            element.getTestStrings().isEmpty()
-            !element.getAssumeSuccess()
-            !element.isNotType()
-            element.isSubstringType()
-    }
-
-    def "Modification of GUI by ResponseAssertion does not throw an exception"() {
-        given:
-            def element = new ResponseAssertion()
-        when:
-            sut.configure(element)
-        then:
-            noExceptionThrown()
-    }
-}