Fix bug where variation count was duplicated

Author: Ecarrion

WooCommerce/Classes/ViewRelated/Products/Variations/GenerateAllVariationsUseCase.swift

@@ -58,11 +58,11 @@ final class GenerateAllVariationsUseCase {
                     onStateChanged(.creating)
                     self.createVariationsRemotely(for: product, variations: variationsToGenerate) { result in
                         switch result {
-                        case .success(let generatedVariations):
+                        case .success(let allVariations):
 
                             // Updates the current product with the up-to-date list of variations IDs.
                             // This is needed in order to reflect variations count changes back to other screens.
-                            let updatedProduct = product.copy(variations: product.variations + generatedVariations.map { $0.productVariationID })
+                            let updatedProduct = product.copy(variations: allVariations.map { $0.productVariationID })
                             onStateChanged(.finished(true, updatedProduct))
 
                         case .failure(let error):

Yosemite/Yosemite/Stores/ProductVariationStore.swift

@@ -168,6 +168,7 @@ private extension ProductVariationStore {
     }
 
     /// Bulk creates the provided array of product variations.
+    /// Returns all product variations on it's completion block.
     ///
     func createProductVariations(siteID: Int64,
                                  productID: Int64,