typo: developer mode

[RararXD]

Description

Changing 'developer mod' into 'developer mode'.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code follows the style of this project
• I have performed a self-review of my code
• [] I have commented my code, particularly in hard-to-understand areas
• [] I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[iewnfod]

You need to learn markdown syntax first

[lightumcc]

You have a good sense of english, but plz try to fix some real bugs next time.