The iOS app login process fails due to a Keychain-related error

The issue may be avoided by creating an .app file with permission to access the Keychain.

If you are building the app under test with Xcode

Please enable Keychain Sharing by following the steps in the article below.
Stack Overflow - SecItemAdd always returns error -34018 in Xcode 8 in iOS 10 simulator

If you are building the app under test with Bitrise

Please refer to the following help page.

In Bitrise, the build app file test fails with “Client has neither application-identifier nor keychain-access-groups entitlements”