Github action not found dotnet csproj file

I use github action release my dotnet packge,but it not found csproj file.
code as:

name: Build And Push Nuget Package

on:
  push:
    branches: [ master ]
  pull_request:
    branches: [ master ]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - name: Setup .NET Core Build Env
      uses: actions/setup-dotnet@v1
      with:
        dotnet-version: 3.1.301
    - name: Restore
      run: |
        pwd
        ls
        stat -c "%s" CkTools/Test/CKTools.Test/CkTools.Test.csproj
        dotnet restore CkTools/CkTools.sln
    - name: UT
      run: dotnet test
    - name: Build
      run: dotnet build CkTools/CkTools.sln --configuration Release --no-restore -o package
    - name: Push
      run: dotnet nuget push "**/*.nupkg" -k '${{secrets.NUGETKEY}}' -s 'https://api.nuget.org/v3/index.json' --skip-duplicate
    - name: Push Symbol 
      run: dotnet nuget push "**/*.snupkg" -k '${{secrets.NUGETKEY}}' -s 'https://api.nuget.org/v3/index.json' --skip-duplicate

it out put in restore step:

/home/runner/.dotnet/sdk/3.1.301/NuGet.targets(282,5): error MSB3202: The project file "/home/runner/work/learningTest/learningTest/CkTools/Test/CkTools.Test/CkTools.Test.csproj" was not found. [/home/runner/work/learningTest/learningTest/CkTools/CkTools.sln]

file exist,form"stat -c “%s” CkTools/Test/CKTools.Test/CkTools.Test.csproj" return 183.

How should I modify it?

action yml file:https://github.com/hjkl950217/learningTest/blob/73491252d6e32a6f0cdd6cc1c17b0ae8f98350c7/.github/workflows/dotnet-core.yml
github url:https://github.com/hjkl950217/learningTest

I created a blank project from 0 and reproduced the problem. This file is missing in Git management, and all files are pushed again to solve the problem