Move SDKMocks into the Components folder

Group the standalone modules that live outside of the app targets under a
single Components folder. Updates the XcodeGen include, the Codecov ignore
path and the Sourcery output path used by the generate-sdk-mocks tool.

Components/SDKMocks/SupportingFiles/target.yml

@@ -0,0 +1,16 @@
+name: SDKMocks
+
+targets:
+  MatrixRustSDKMocks:
+    type: library.static
+    platform: iOS
+
+    dependencies:
+    - package: MatrixRustSDK
+
+    settings:
+      base:
+        PRODUCT_NAME: MatrixRustSDKMocks
+
+    sources:
+      - ../Sources