4112 Split some Cirrus script steps (cla: yes)

4113 [in_app_purchase] Initialize SKError with correct data type (cla: yes, waiting for tree to go green, p: in_app_purchase, platform-ios)

4114 [in_app_purchase] Added priceCurrencySymbol to SkuDetailsWrapper (cla: yes, waiting for tree to go green, p: in_app_purchase, platform-android)

4115 [in_app_purchase] Add currencySymbol to ProductDetails (cla: yes, waiting for tree to go green, p: in_app_purchase)

4116 [flutter_plugin_tools] Migrate firebase-test-lab to new base command (cla: yes)

4117 [image_picker] Fixed IOException when cache directory is removed (cla: yes, waiting for tree to go green, p: image_picker, platform-android)