CIS will likely amend it on your behalf understanding that you filed it on your own and without counsel. They may require you to submit a new I-765 with the amendment and a new signature but they won't deny it.
Don't worry, such minor errors are common. In all likelihood you won't even get an RFE for it. USCIS will correct that on its own.
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.