bump package target to iOS 9 and update testing packages (#802)

* bump package target to iOS 9 and update testing packages

* update the changelog

CHANGELOG.md

@@ -1,10 +1,14 @@
 # master
 *Please add new entries at the top.*
 
+1. Bump min. deployment target to iOS 9 when using swift packages to silence Xcode 12 warnings. Update Quick & Nibmle to the latest version when using swift packages.
+
 1. Fix a debug assertion in `Lock.try()` that could be raised in earlier OS versions (< iOS 10.0, < macOS 10.12). (#747, #788)
 
    Specifically, ReactiveSwift now recognizes `EDEADLK` as expected error code from `pthread_mutex_trylock` alongside `0`, `EBUSY` and `EAGAIN`.
 
+2. 
+
 # 6.3.0
 1. `Property` and `MutableProperty` can now be used as property wrapper. Note that they remain a reference type container, so it may not be appropriate to use them in types requiring value semantics. (#781)
    ```swift

Package.resolved

@@ -6,17 +6,17 @@
         "repositoryURL": "https://github.com/Quick/Nimble.git",
         "state": {
           "branch": null,
-          "revision": "72f5a90d573f7f7d70aa6b8ad84b3e1e02eabb4d",
-          "version": "8.0.9"
+          "revision": "7a46a5fc86cb917f69e3daf79fcb045283d8f008",
+          "version": "8.1.2"
         }
       },
       {
         "package": "Quick",
         "repositoryURL": "https://github.com/Quick/Quick.git",
         "state": {
           "branch": null,
-          "revision": "09b3becb37cb2163919a3842a4c5fa6ec7130792",
-          "version": "2.2.1"
+          "revision": "0038bcbab4292f3b028632556507c124e5ba69f3",
+          "version": "3.0.0"
         }
       }
     ]

Package.swift

@@ -4,13 +4,13 @@ import PackageDescription
 let package = Package(
     name: "ReactiveSwift",
     platforms: [
-        .macOS(.v10_10), .iOS(.v8), .tvOS(.v9), .watchOS(.v2)
+        .macOS(.v10_10), .iOS(.v9), .tvOS(.v9), .watchOS(.v2)
     ],
     products: [
         .library(name: "ReactiveSwift", targets: ["ReactiveSwift"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/Quick/Quick.git", from: "2.2.1"),
+        .package(url: "https://github.com/Quick/Quick.git", from: "3.0.0"),
         .package(url: "https://github.com/Quick/Nimble.git", from: "8.0.9"),
     ],
     targets: [