FFI 0.12.0 bump

- FFI version bumped to 0.12.0

Example/ZcashLightClientSample/ZcashLightClientSample.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -176,7 +176,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/Electric-Coin-Company/zcash-light-client-ffi",
       "state" : {
-        "revision" : "2487d2cd04128c6e5d7a53d29b11d8c06197b840"
+        "revision" : "11b0db058288b12ada9c5a95ed56f17f82d2868f",
+        "version" : "0.12.0"
       }
     }
   ],

Package.swift

@@ -16,7 +16,7 @@ let package = Package(
     dependencies: [
         .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.24.2"),
         .package(url: "https://github.com/stephencelis/SQLite.swift.git", from: "0.15.3"),
-        .package(url: "https://github.com/Electric-Coin-Company/zcash-light-client-ffi", revision: "2487d2cd04128c6e5d7a53d29b11d8c06197b840")
+        .package(url: "https://github.com/Electric-Coin-Company/zcash-light-client-ffi", from: "0.12.0")
     ],
     targets: [
         .target(