Use “I'ma” instead of “Imma”.
The reviewed Genius spelling guide recommends this form.
Example
[Verse]
Imma go[Verse]
I'ma goThe fix
In the workbench this finding carries one control, labelled Replace with I'ma. The fix is classified as safe, so pressing it applies the edit directly — one press, one undo step.
Source
The guideline this rule enforces, as cited on every finding it reports:
Use standardized spellings verified Preferred spellings with contextual exceptions