Move kotlin.test common annotations tests

Place them in tests of kotlin-test-annotations-common, so that every
platform module that implements that common module (e.g. kotlin-test-junit,
kotlin-test-junit5, kotlin-test-testng) gets these tests run.

Improve test for BeforeTest/AfterTest annotations to check that they are
invoked before/after _each_ test method.

#KT-27629

libraries/kotlin.test/common/src/test/kotlin/kotlin/test/tests/AnnotationsTest.kt

@@ -1,40 +0,0 @@
-/*
- * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
- */
-
-package kotlin.test.tests
-
-import kotlin.test.*
-
-private var value = 5
-
-class AnnotationsTest {
-
-    @BeforeTest
-    fun setup() {
-        value *= 2
-    }
-
-    @AfterTest
-    fun teardown() {
-        value /= 2
-    }
-
-    @Test
-    fun testValue() {
-        assertEquals(10, value)
-    }
-
-    @Test
-    fun testValueAgain() {
-        assertEquals(10, value)
-    }
-
-    @Ignore
-    @Test
-    fun testValueWrong() {
-        assertEquals(20, value)
-    }
-
-}