fix: bump iOS version to 15 (#33)

Author: jcesarmobile

Sources/CapacitorPluginTools/PackageFileGenerator.swift

@@ -14,7 +14,7 @@ public class PackageFileGenerator {
 
             let package = Package(
                 name: "\(packageName)",
-                platforms: [.iOS(.v14)],
+                platforms: [.iOS(.v15)],
                 products: [
                     .library(
                         name: "\(packageName)",

Tests/CapacitorPluginToolsTests/PackageFileGenerator.swift

@@ -20,7 +20,7 @@ struct PackageFileGeneratorTests {
 
         let package = Package(
             name: "CapacitorAppPlugin",
-            platforms: [.iOS(.v14)],
+            platforms: [.iOS(.v15)],
             products: [
                 .library(
                     name: "CapacitorAppPlugin",