我正在使用Firebase构建一个小项目，该项目过去可以在iOS和android模拟器上运行，但是由于几天前，它在iOS上不再工作，并且在pod安装后显示了此错误：
正在运行Pod安装... CocoaPods的输出： ↳ 准备
Analyzing dependencies
Inspecting targets to integrate
Using `ARCHS` setting to build architectures of target `Pods-Runner`: (``)
Finding Podfile changes
- Flutter
- cloud_firestore
- firebase_auth
- firebase_core
Fetching external sources
-> Fetching podspec for `Flutter` from `.symlinks/flutter/ios`
-> Fetching podspec for `cloud_firestore` from `.symlinks/plugins/cloud_firestore/ios`
-> Fetching podspec for `firebase_auth` from `.symlinks/plugins/firebase_auth/ios`
-> Fetching podspec for `firebase_core` from `.symlinks/plugins/firebase_core/ios`
Resolving dependencies of `Podfile`
Setting up CocoaPods master repo
$ /usr/bin/git remote set-url origin https://github.com/CocoaPods/Specs.git
[!] Failed: /usr/bin/git remote set-url origin https://github.com/CocoaPods/Specs.git
$ /usr/bin/git checkout master
[!] Failed: /usr/bin/git checkout master
[!] Unable to add a source with url `https://github.com/CocoaPods/Specs.git` named `master-1`.
(The `master` repo is not a git repo.)
You can try adding it manually in `/Users/myname/.cocoapods/repos` or via `pod repo add`.
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/sources_manager.rb:40:in `rescue in find_or_create_source_with_url'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/sources_manager.rb:43:in `find_or_create_source_with_url'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:173:in `block in sources'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:172:in `map'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:172:in `sources'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:938:in `block in resolve_dependencies'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/user_interface.rb:64:in `section'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:937:in `resolve_dependencies'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer/analyzer.rb:118:in `analyze'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer.rb:398:in `analyze'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer.rb:221:in `block in resolve_dependencies'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/user_interface.rb:64:in `section'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer.rb:220:in `resolve_dependencies'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/installer.rb:156:in `install!'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/command/install.rb:51:in `run'
/Library/Ruby/Gems/2.3.0/gems/claide-1.0.3/lib/claide/command.rb:334:in `run'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/lib/cocoapods/command.rb:52:in `run'
/Library/Ruby/Gems/2.3.0/gems/cocoapods-1.7.5/bin/pod:55:in `<top (required)>'
/usr/local/bin/pod:22:in `load'
/usr/local/bin/pod:22:in `<main>'
CocoaPods错误输出： ↳ 致命的：不是git存储库（或任何父目录）：.git 致命的：不是git存储库（或任何父目录）：.git
运行pod安装时出错 在iPhoneXʀ上启动应用程序时出错。