Move HttpServiceProxyFactoryExtensions.kt to spring-web module

HttpServiceProxyFactoryExtensions.kt has been mistakenly created
in spring-webflux module instead of spring-web, breaking JPMS for
WebFlux users.

This commit moves this file and related tests to the spring-web
module.

Closes gh-30042

spring-web/src/main/kotlin/org/springframework/web/service/invoker/HttpServiceProxyFactoryExtensions.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.web.service.invoker
+
+/**
+ * Extension for [HttpServiceProxyFactory.createClient] providing a `createClient<Foo>()` variant.
+ *
+ * @author Sebastien Deleuze
+ * @since 6.0.5
+ */
+inline fun <reified T : Any> HttpServiceProxyFactory.createClient(): T =
+	createClient(T::class.java)

spring-web/src/test/kotlin/org/springframework/web/service/invoker/HttpServiceProxyFactoryExtensionsTests.kt

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2002-2023 the original author or authors.
+ *
+ * Licensed 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
+ *
+ *      https://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.springframework.web.service.invoker
+
+import io.mockk.every
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.jupiter.api.Test
+
+/**
+ * Tests for [HttpServiceProxyFactory] Kotlin extensions.
+ *
+ * @author Sebastien Deleuze
+ */
+class HttpServiceProxyFactoryExtensionsTests {
+
+	private val proxyFactory = mockk<HttpServiceProxyFactory>()
+
+	@Test
+	fun `createClient extension`() {
+		every { proxyFactory.createClient(String::class.java) } returns ""
+		proxyFactory.createClient<String>()
+		verify { proxyFactory.createClient(String::class.java) }
+	}
+
+}