How to publish maven library into GitHub Actions locally?

I have a GitHub Actions script to build an Android app, but I need to include specific prebuilt libraries (ktmidi and rtmidi) that I prebuilt on my local machine before starting work on the project. How can I publish these libraries to ensure the Android app builds correctly?

My GitHub Actions code:

...
jobs:
  build_android:
    name: Assemble android release, send it into App Distribution and notify other team
    runs-on: ubuntu-22.04
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4
        with:
          submodules: recursive

      - name: Install Dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y build-essential autoconf libtool pkg-config libasound2-dev libjack-jackd2-dev cmake ninja-build doxygen

      - name: Grant Permission for gradlew
        run: chmod +x gradlew

      - name: Initialize and Update Git Submodules
        run: git submodule update --init --recursive

      - name: Assemble Release
        run: ./gradlew assembleRelease ...

Old version:

jobs:
  build_android:
    name: Assemble android release, send it into App Distribution and notify other team
    runs-on: ubuntu-22.04
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4
        with:
          submodules: recursive

      - name: Install Dependencies
        run: |
          sudo apt-get update
          sudo apt-get install -y build-essential autoconf libtool pkg-config libasound2-dev libjack-jackd2-dev cmake ninja-build doxygen
      - name: Setup NDK Workaround
        run: sudo mkdir -p /usr/local/lib/android/sdk/ndk && sudo chmod 777 /usr/local/lib/android/sdk/ndk

      - name: Build and Publish ktmidi to Local Maven
        run: |
         ls -l ktmidi/
         sed -i "s/signing {}/signing { sign(publishing.publications) }/" ktmidi/build.gradle.kts
         sed -i "s/signing {}/signing { sign(publishing.publications) }/" ktmidi-jvm-desktop/build.gradle
         sed -i "s/signing {}/signing { sign(publishing.publications) }/" ktmidi-native-ext/build.gradle.kts
         ./build-rtmidi.sh
         ./gradlew --warning-mode all build publishToMavenLocal
        env:
          GITHUB_TOKEN: ${{ secrets.MAVEN_PAT }}
          OSSRH_USERNAME: ${{ secrets.OSSRH_USERNAME }}
          OSSRH_PASSWORD: ${{ secrets.OSSRH_PASSWORD }}
          SIGNING_KEY_ID: ${{ secrets.SIGNING_KEY_ID }}
          SIGNING_PASSWORD: ${{ secrets.SIGNING_PASSWORD }}
          SIGNING_SECRET_KEY_RING_FILE: ${{ secrets.SIGNING_SECRET_KEY_RING_FILE }}

I add download RtMidi 4.0.0 task to publish this library locally, but I get issue: 'rtmidi/rtmidi_c.h' file not found.

I'm the ktmidi developer. Since you seem to have "downloaded" the repository content from GitHub, it would not contain those git submodules. There are some dependencies under external directory, and if your checkout directory there is empty, then you need to get the submodules too.

I would recommend to "clone" the git repository (git clone [the-ktmidi-repo-url]), and run git submodule update --init --recursive to make sure that they are checked out as well.