fix-typo in "flutter analyze --suggestions" command on Android Java Gradle migration guide Page

[MS-Rex]

Description of what this PR is changing or adding, and why:

_Issues fixed by this PR (if any): fix typo in "flutter analyze --suggestions" command on Android Java Gradle migration guide Page

_PRs or commits this PR depends on (if any):No

Presubmit checklist

• This PR is marked as draft with an explanation if not meant to land until a future stable release.
• This PR doesn’t contain automatically generated corrections (Grammarly or similar).
• This PR follows the Google Developer Documentation Style Guidelines — for example, it doesn’t use i.e. or e.g., and it avoids I and we (first person).
• This PR uses semantic line breaks of 80 characters or fewer.