Get rid of duplicated file names in spec tests

Otherwise, corresponding IDE tests would fail on creation duplicated
files in the same directory

compiler/tests-spec/build.gradle.kts

@@ -28,6 +28,8 @@ sourceSets {
     "test" { projectDefault() }
 }
 
+testsJar()
+
 projectTest(parallel = true) {
     workingDir = rootDir
 }

compiler/tests-spec/testData/diagnostics/linked/declarations/classifier-declaration/class-declaration/abstract-classes/p-2/neg/1.1.kt

@@ -81,7 +81,7 @@ class ImplBaseCase2() : Base() {
     }
 }
 
-// FILE: TestCase.kt
+// FILE: TestCase3.kt
 // TESTCASE NUMBER: 3
 
 package testPackCase3
@@ -120,7 +120,7 @@ fun case3() {
     }
 }
 
-// FILE: TestCase.kt
+// FILE: TestCase4.kt
 // TESTCASE NUMBER: 4
 package testPackCase4
 <!REDUNDANT_MODIFIER!>open<!> abstract class Base {

compiler/tests-spec/testData/diagnostics/linked/declarations/classifier-declaration/class-declaration/abstract-classes/p-2/neg/1.2.kt

@@ -11,7 +11,7 @@
  * DESCRIPTION: Abstract classes may contain abstract members, which should be implemented in an anonymous class that inherits from that abstract type
  */
 
-// FILE: TestCase.kt
+// FILE: TestCase1.kt
 // TESTCASE NUMBER: 1
 package testPackCase1
 private abstract class Base {
@@ -48,7 +48,7 @@ fun case1() {
 }
 
 
-// FILE: TestCase.kt
+// FILE: TestCase2.kt
 /*
  * TESTCASE NUMBER: 2
  * NOTE: property is not implemented
@@ -90,7 +90,7 @@ fun case2() {
 }
 
 
-// FILE: TestCase.kt
+// FILE: TestCase3.kt
 // TESTCASE NUMBER: 3
 package testPackCase3
 private abstract class Base {

compiler/tests-spec/testData/diagnostics/linked/declarations/classifier-declaration/class-declaration/abstract-classes/p-2/neg/1.3.kt

@@ -11,7 +11,7 @@
  * DESCRIPTION: attempt to implement abstract members with invalid types
  */
 
-// FILE: TestCase.kt
+// FILE: TestCase1.kt
 // TESTCASE NUMBER: 1
 package testPackCase1
 abstract class Base {
@@ -37,7 +37,7 @@ class Case1 : Base() {
 
 
 
-// FILE: TestCase.kt
+// FILE: TestCase2.kt
 // TESTCASE NUMBER: 2
 package testPackCase2
 abstract class Base {
@@ -53,7 +53,7 @@ class Case2(override val a: String, override var b: <!VAR_TYPE_MISMATCH_ON_OVERR
     }
 }
 
-// FILE: TestCase.kt
+// FILE: TestCase3.kt
 // TESTCASE NUMBER: 3
 package testPackCase3
 abstract class Base {

compiler/tests-spec/testData/diagnostics/linked/expressions/constant-literals/the-types-for-integer-literals/p-1/pos/2.5.kt

@@ -11,7 +11,7 @@
  * HELPERS: checkType
  */
 
-// FILE: functions.kt
+// FILE: fileWithFunctions.kt
 
 package functions
 

compiler/tests-spec/testData/diagnostics/linked/expressions/prefix-expressions/prefix-increment-expression/p-4/neg/1.1.kt

@@ -13,7 +13,7 @@
  */
 
 
-// FILE: TestCase.kt
+// FILE: TestCase1.kt
 // TESTCASE NUMBER: 1
 package testPackCase1
 
@@ -36,7 +36,7 @@ class Case1() {
     var a: A = A()
 }
 
-// FILE: TestCase.kt
+// FILE: TestCase2.kt
 // TESTCASE NUMBER: 2
 package testPackCase2
 

compiler/tests-spec/testData/diagnostics/linked/expressions/try-expression/p-8/neg/1.1.kt

@@ -12,7 +12,7 @@
  * DESCRIPTION: The type of the try-expression is the least upper bound of the types of the last expressions of the try body and the last expressions of all the catch blocks
  */
 
-// FILE: TestCase.kt
+// FILE: TestCase1.kt
 // TESTCASE NUMBER: 1
 package testPackCase1
 
@@ -38,7 +38,7 @@ fun case1() {
     }
 }
 
-// FILE: TestCase.kt
+// FILE: TestCase2.kt
 // TESTCASE NUMBER: 2
 package testPackCase2
 
@@ -66,7 +66,7 @@ fun case2() {
 }
 
 
-// FILE: TestCase.kt
+// FILE: TestCase3.kt
 // TESTCASE NUMBER: 3
 // ISSUES: KT-35494
 package testPackCase3