Standardised ReplaySubject double subscribe behaviour

Thanks, @jasdev, for the heads-up!

Sources/Entwine/Operators/ReplaySubject.swift

@@ -58,7 +58,6 @@ extension ReplaySubject: Publisher {
 
         guard !subscriberIdentifiers.contains(subscriber.combineIdentifier) else {
             subscriber.receive(subscription: Subscriptions.empty)
-            subscriber.receive(completion: .finished)
             return
         }
 

Tests/EntwineTests/ReplaySubjectTests.swift

@@ -451,6 +451,28 @@ final class ReplaySubjectTests: XCTestCase {
 
         XCTAssertEqual(results2.recordedOutput, results1.recordedOutput)
     }
+
+    func testDuplicateSubscriptionMatchesControl() {
+
+        var subject: ReplaySubject<Int, Never>! = nil
+        var control: PassthroughSubject<Int, Never>! = nil
+
+        let results1 = scheduler.createTestableSubscriber(Int.self, Never.self)
+        let results2 = scheduler.createTestableSubscriber(Int.self, Never.self)
+
+        scheduler.schedule(after: 100) { subject = ReplaySubject(maxBufferSize: 1) }
+        scheduler.schedule(after: 100) { control = PassthroughSubject() }
+        scheduler.schedule(after: 200) { subject.subscribe(results1) }
+        scheduler.schedule(after: 200) { control.subscribe(results2) }
+        scheduler.schedule(after: 300) { subject.subscribe(results1) }
+        scheduler.schedule(after: 300) { control.subscribe(results2) }
+        scheduler.schedule(after: 400) { subject = nil }
+        scheduler.schedule(after: 400) { control = nil }
+
+        scheduler.resume()
+
+        XCTAssertEqual(results2.recordedOutput, results1.recordedOutput)
+    }
 
     func testSendSubscriptionInitialDemandUnlimitedBehaviorMatchesControl() {