Edge Zone can not register iso 



##### ISSUE TYPE

 * Bug Report
 

##### COMPONENT NAME
API,  UI,

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##### CLOUDSTACK VERSION
main ,4.18.0.0 RC1

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We created Edge Zone named edge1,when registered iso , we can not choose the edge1(only all zone), then it rasied error:
Unable to find image store to download template null 

![Uploading image.png…]()

