Google CloudBuild doesn't detect Licence

Bug description

Context

I'm trying to setup the CI pipeline in Google CloudBuild.

Steps

I've followed carefully all the steps porting the gitlab pipeline example over.
I've generated and activated the license successfully. The generation was done in a CloudBuild runner and the activation manually in the unity website.
I've encoded to base64 the licence and added it as a secret environment variable. Then decoded it before saving it to disk.

Findings

The before_script.sh is running fine and writing to disk the licence at: /root/.local/share/unity3d/Unity/Unity_lic.ulf

I've also inspected the licence by cat /root/.local/share/unity3d/Unity/Unity_lic.ulf and it matches with the one i've downloaded.

The Problem

The problem i'm having is that when the build.sh is running it seems that doesn't detect the license file located in /root/.local/share/unity3d/Unity/Unity_lic.ulf and so it tries to generate a new license to activate.

Here is the output I'm getting:

docker.io/unityci/editor:2021.3.6f1-webgl-1.0.1
+ mkdir -p /root/.cache/unity3d
+ mkdir -p /root/.local/share/unity3d/Unity/
+ set +x
Writing '$UNITY_LICENSE' to license file /root/.local/share/unity3d/Unity/Unity_lic.ulf
+ echo 'Building for WebGL'
+ export BUILD_PATH=/workspace/Builds/WebGL/
+ BUILD_PATH=/workspace/Builds/WebGL/
+ mkdir -p /workspace/Builds/WebGL/
Building for WebGL
+ cat /root/.local/share/unity3d/Unity/Unity_lic.ulf
[REDACTED LICENCE OUTPUT]

Branch:                  2021.3/staging
Build type:              Release
Batch mode:              YES
System name:             Linux
Distro version:          #1 SMP Debian 5.10.127-1 (2022-06-30)
Kernel version:          5.10.0-16-cloud-amd64
Architecture:            x86_64
Available memory:        3930 MB
[LicensingClient] Channel doesn't exist: "LicenseClient-root"
[Licensing::Module] Successfully launched the LicensingClient (PId: 59)
[SignatureVerifier] Application signature verification not supported on this platform.
[LicensingClient] Handshaking with LicensingClient (version: 1.9.0+249add7)
[Licensing::Module] Successfully connected to LicensingClient on channel: "LicenseClient-root" (connect: 1.37s, validation: 0.20s, handshake: 0.00s)
[Licensing::Module] Connected to LicensingClient (PId: 59, launch time: 0.00, total connection time: 1.57s)
Entitlement-based licensing initiated
[Licensing::Module] Error: Access token is unavailable
[LicensingClient] Licenses updated successfully
[UnityConnectServicesConfig] config is NOT valid, switching to default
Cancelling DisplayDialog: Failed to activate/update license Missing or bad username or password. Please try again using valid credentials or contact support@unity3d.com
This should not be called in batch mode.

cloud build:

steps:
  - name: unityci/editor:2021.3.6f1-webgl-1.0.1
    secretEnv: ['UNITY_LICENCE']
    entrypoint: "bash"
    args:
      - "-c"
      - |
        chmod +x ./ci/before_script.sh ./ci/build.sh && ./ci/before_script.sh && ./ci/build.sh

Ugly workaround

If i run the job by using "docker in docker" it seems to work correctly, for example, given the following configuration:

steps:
  - name: gcr.io/cloud-builders/docker
    secretEnv: ['UNITY_LICENCE']
    entrypoint: 'bash'
    args:
      - -c
      - |
         docker run --ipc=host \
            -e BUILD_TARGET="$$BUILD_TARGET" \
            -e BUILD_NAME=$$BUILD_NAME \
            -e UNITY_DIR=$$UNITY_DIR \
            -e VERSION_NUMBER_VAR=$$VERSION_NUMBER_VAR \
            -e VERSION_BUILD_VAR=$$VERSION_NUMBER_VAR \
            -e UNITY_LICENCE="$$UNITY_LICENCE" \
            -w /project/ \
            -v /workspace:/project/ \
            unityci/editor:2021.3.6f1-webgl-1.0.1 \
            /bin/bash -c "chmod +x /project/ci/before_script.sh /project/ci/build.sh && /project/ci/before_script.sh && /project/ci/build.sh"
    env:
      - 'BUILD_TARGET=WebGL'
      - 'BUILD_NAME=ShoppingMall'
      - 'UNITY_DIR=/project'
      - 'VERSION_NUMBER_VAR=$SHORT_SHA'
      - 'VERSION_BUILD_VAR=$REVISION_ID'

Steps to reproduce

Simply try to run the following job in cloudbuild:

steps:
  - name: unityci/editor:2021.3.6f1-webgl-1.0.1
    env:
      - 'UNITY_LICENCE=LICENCE_BASE64_HERE'
    entrypoint: "bash"
    args:
      - "-c"
      - |
        chmod +x ./ci/before_script.sh ./ci/build.sh && ./ci/before_script.sh && ./ci/build.sh

alter the before_script.sh to decode the variable, for example:

echo -n $UNITY_LICENCE | base64 -d | tr -d '\r' > ${unity_license_destination}

Expected behavior

The cloudbuild runner picks up the license when running the build.sh script

Additional details

game-ci / documentation