const dbMigrateTask = new awsx.ecs.FargateTaskDefinition(
  'setup-db',
  {
    container: {
      image: image,
      command: pulumi
        .all([rdsInstance.endpoint])
        .apply(([url]) => ['/bin/sh', '-c', `DATABASE_URL=${url} npx prisma migrate deploy`]),
      environment: [
        {
          name: 'DATABASE_URL',
          value: rdsInstance.endpoint.apply(
            (v) => `postgresql://${rdsSettings.username}:${rdsSettings.password}@${v}/${rdsSettings.database}`,
          ),
        },
      ],
    },
  },
  { dependsOn: [rdsInstance] },
)

dbMigrateTask.run({ cluster: cluster })

Error: Cannot call '.get' during update or preview.
    To manipulate the value of this Output, use '.apply' instead.

.get

.apply

TF_LOG=TRACE pulumi up --logtostderr -v=9 2> out.txt