Refactoring Responsive Grid XML specs for more flexibility

It merges portrait and landscape XML specs for responsive grid. This update allows the responsive grid to rely on other properties like aspect ratio and not solely the orientation from resource qualifiers.

Bug: 299889733
Flag: ACONFIG com.android.launcher3.enable_responsive_workspace TEAMFOOD
Test: CalculatedAllAppsSpecTest
Test: CalculatedFolderSpecTest
Test: CalculatedHotseatSpecTest
Test: CalculatedWorkspaceSpecTest
Test: AllAppsSpecsTest
Test: FolderSpecTest
Test: HotseatSpecsTest
Test: WorkspaceSpecsTest
Change-Id: I39ee54d49c9d2a54fcbe91c8a1327a21a8126032