警告文

[!] Automatically assigning platform `iOS` with version `15.4` on target `LicensePlist-Demo` because no platform was specified. Please specify a platform for this target in your Podfile. See `https://guides.cocoapods.org/syntax/podfile.html#platform`.

解決方法

警告文で表示されているバージョンをPodfileファイルに記載する

  # Uncomment the next line to define a global 
  platform for your project
+ platform :ios, '14.0'

  target 'LicensePlist-Demo' do
    # Comment the next line if you don't want to use 
  dynamic frameworks
    use_frameworks!

    # Pods for LicensePlist-Demo
    pod 'LicensePlist'

  end