TL:DR One of ENV vars is not dumping in github actions workflow, and I could not figure why.

Currently, I’m working on integrating with our scripts GH Actions, and one task is to hand over environment variables to our deployment scripts so that Ansible can use it
​I made a short test, where I dump all the “env” context. For test purposes, I created the workflow, job, and step variables. Interestingly, when I dump the env context, the step variable is not included in the output.

GHA workflow example:

# Controls when the action will run. Triggers the workflow on push or pull request
# events but only for the master branch
on:
  push:
    branches: [ master ]
  pull_request:
    branches: [ master ]
this is a workflow variable
env:

WORKFLOW_VAR: "workflow variable"

ANOTHER_WF_VAR: "another environment variable available to all jobs and steps in the workflow"
A workflow run is made up of one or more jobs that can run sequentially or in parallel
jobs:
This workflow contains a single job called "build"
build:

# The type of runner that the job will run on

runs-on: build
# this is a job variable
env:
  JOB_VAR: "job variable"
  ANOTHER_JOB_VAR: "another environment variable that is available only to all steps in build job"    
# Steps represent a sequence of tasks that will be executed as part of the job
steps:
# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
- uses: actions/checkout@v2
# Runs a single command using the runners shell
- name: Run a one-line script
  # this is a step variable
  env:
    STEP_VAR: "step variable"
    ANOTHER_STEP_VAR: "another environment variable that is available only to the step job"
  run: echo Hello, $STEP_VAR!
# Runs a set of commands using the runners shell
- name: Run a multi-line script
  run: |
    echo Add other actions to build,
    echo test, and deploy your project.
    echo $ANOTHER_JOB_VAR
    uname -a
- name: Dump env context
  env:
    STEP_VAR_FOR_ENV_DUMP: "this is a step var for the env context dump step"
    ENV_CONTEXT: ${{ toJson(env) }}
  run: echo "$ENV_CONTEXT"
- name: Dump GitHub context
  env:
    STEP_VAR_FOR_DUMP: "step var only for the GitHub context dump step"
    GITHUB_CONTEXT: ${{ toJson(github) }}
  run: echo "$GITHUB_CONTEXT"

Run results:

image909×526 35.6 KB

Dump env context step, should contain STEP_VAR_FOR_ENV_DUMP, but it does not.
Any ideas why?