image_builder: fix blob command

[nalajcie]

Description

• image_builder: fix blob command
• image_builder: small typing/linter fixes

Motivation and Context

JIRA: CI-494

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (refactoring, style fixes, git/CI config, submodule management, no code logic changes)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: armv7a9-zynq7000-qemu: add blob plo command example usage phoenix-rtos-project#1211
• Tested by hand on: zynq7000-qemu.

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• I will merge this PR by myself when appropriate.

[github-actions]

Unit Test Results

7 741 tests  +16   7 026 ✅ +16   41m 11s ⏱️ + 4m 5s
  461 suites +16     715 💤 ± 0 
    1 files   ± 0       0 ❌ ± 0 

Results for commit c3163e3. ± Comparison against base commit dfc551a.

♻️ This comment has been updated with latest results.

[ziemleszcz]

Looks OK except debug print and one extra space before data map.

[nalajcie]

Looks OK except debug print and one extra space before data map.

I've noticed the extra space but couldn't think of not over-complicated way to remove it (and plo didn't have problem).

I've proposed some solution (with extra comment to avoid removing it in the future).