[MOB-10402] Fix test plan path in xcscheme files

Author: sumeruchat

swift-sdk.xcodeproj/xcshareddata/xcschemes/endpoint-tests.xcscheme

@@ -13,7 +13,7 @@
       shouldUseLaunchSchemeArgsEnv = "YES">
       <TestPlans>
          <TestPlanReference
-            reference = "container:../endpoint-tests.xctestplan"
+            reference = "container:tests/endpoint-tests.xctestplan"
             default = "YES">
          </TestPlanReference>
       </TestPlans>

swift-sdk.xcodeproj/xcshareddata/xcschemes/swift-sdk.xcscheme

@@ -112,7 +112,7 @@
       </CodeCoverageTargets>
       <TestPlans>
          <TestPlanReference
-            reference = "container:../swift-sdk.xctestplan"
+            reference = "container:tests/swift-sdk.xctestplan"
             default = "YES">
          </TestPlanReference>
       </TestPlans>