I think it might be enough to open up your project up in VSCODE and change the ‘IPHONEOS_DEPLOYMENT_TARGET’ to 9.0 in all 3 places where it is present. In addition check your AppFrameworkInfo.plist file and set the MinimumiOSVersion to 9.0 there as well.
If you wish to create a podfile through Codemagic however, then you might try to put this into your pre build script for the first run (and remove it later):
cd ios && pod init && git add . && git commit -m “Add Podfile to project” && git push
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