開発環境

OS: MacOS
Flutter: 3.0.4
Flutter Channel: Stable
Dart: 2.17.5
Android Studio: Artic Fox | 2020.3.1 Patch4

エラーメッセージ

Automatically signing iOS for device deployment using specified development team in Xcode project: XXXXXXX
Running pod install...
Running Xcode build...
Xcode build done.                                            8.3s
Failed to build iOS app
Error output from Xcode build:
↳
    ** BUILD FAILED **


Xcode's output:
↳
    Writing result bundle at path:
    	/var/folders/xz/8ytcyfm94hj21ggqskb0fgsc0000gn/T/flutter_tools.XxfdYA/flutter_ios_build_temp_dirhG8RAE/temporary_xcresult_bundle

    note: Using new build system
    note: Planning
    note: Build preparation complete
    note: Building targets in parallel
    /Users/ユーザ名/AndroidStudioProjects/アプリ名/ios/Flutter/Release.xcconfig:3:1: error: could not find included file 'Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig' in search paths
    /Users/ユーザ名/AndroidStudioProjects/アプリ名/ios/Flutter/Release.xcconfig:3:1: error: could not find included file 'Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig' in search paths
    /Users/ユーザ名/AndroidStudioProjects/アプリ名/ios/Flutter/Release.xcconfig:3:1: error: could not find included file 'Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig' in search paths

    Result bundle written to path:
    	/var/folders/xz/8ytcyfm94hj21ggqskb0fgsc0000gn/T/flutter_tools.XxfdYA/flutter_ios_build_temp_dirhG8RAE/temporary_xcresult_bundle


Could not build the precompiled application for the device.
Error (Xcode): could not find included file 'Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig' in search paths
/Users/ユーザ名/AndroidStudioProjects/アプリ名/ios/Flutter/Release.xcconfig:2:0


Error running application on 実機名.

原因

includeに指定したファイルのパスが誤っていることが原因です。
下記エラーメッセージではRelease.xcconfigにてincludeに指定しているPods-Runner.profile.xcconfigが見つからないよ、と言っています。

Error (Xcode): could not find included file 'Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig' in search paths
/Users/ユーザ名/AndroidStudioProjects/アプリ名/ios/Flutter/Release.xcconfig:2:0

実際にファイルの階層を確認してみると頭のPods/が抜けていることがわかります。
※ Release.xcconfigから見た相対パス

対処法

ios/Flutter/Release.xcconfigにてincludeに指定しているファイルのパスを修正します。
Pods-Runner.profile.xcconfigの先頭にPods/を追加します。

修正前

#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
#include "Generated.xcconfig"
// ↓修正対象
#include "Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig"

修正後

#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
#include "Generated.xcconfig"
// ↓先頭にPods/を追加
#include "Pods/Target Support Files/Pods-Runner/Pods-Runner.profile.xcconfig"