Aparece el error "No autorizado" al ejecutar el análisis de SonarQube en el contenedor Docker con GitLab Runner

Question

Estoy intentando ejecutar un análisis de SonarQube en un contenedor Docker usando GitLab Runner, pero encuentro el siguiente error:

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'GlobalServerSettings' defined in org.sonar.scanner.bootstrap.GlobalServerSettingsProvider: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.sonar.scanner.bootstrap.GlobalServerSettings]: Factory method 'provide' threw exception; nested exception is Not authorized. Please check the properties sonar.login and sonar.password.
    at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:658)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:638)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1352)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1195)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
    ... 70 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.sonar.scanner.bootstrap.GlobalServerSettings]: Factory method 'provide' threw exception; nested exception is Not authorized. Please check the properties sonar.login and sonar.password.
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:653)
    ... 84 more
Caused by: Not authorized. Please check the properties sonar.login and sonar.password.
Cleaning up project directory and file based variables
00:01
ERROR: Job failed: exit code 1

Mi GitLab Runner se ejecuta en un contenedor Docker y tengo SonarQube también ejecutándose en un contenedor Docker. He configurado mi archivo .gitlab-ci.yml de la siguiente manera:

sonarqube-check:
  tags:
    - my-api
  image:
    name: sonarsource/sonar-scanner-cli:5.0
    entrypoint: [""]
  variables:
    SONAR_USER_HOME: "${CI_PROJECT_DIR}/.sonar"
    GIT_DEPTH: "0"
    SONAR_TOKEN: "$SONARQUBE_TOKEN"
  cache:
    key: "${CI_JOB_NAME}"
    paths:
      - .sonar/cache
  script:
    - sonar-scanner -X 
  rules:
    - if: $CI_COMMIT_BRANCH == 'main'

Mi archivo sonar-project.properties se ve así:

sonar.projectKey=my-api
sonar.qualitygate.wait=true

Pasé la URL del host de SonarQube y el token como variables de entorno. ¿Alguien puede ayudarme a comprender qué podría estar causando este error "No autorizado" y cómo resolverlo?