The easiest way to tweak this in my opinion (imho) is to edit the .git/config file in your repository. Look for the entry you messed up and just tweak the URL.
On my machine in a repo I regularly use it looks like this:
KidA% cat .git/config
[core]
repositoryformatversion = 0
filemode = true
bare = false
logallrefupdates = true
ignorecase = true
autocflg = true
[remote "origin"]
url = ssh://localhost:8888/opt/local/var/git/project.git
#url = ssh://xxx.xxx.xxx.xxx:80/opt/local/var/git/project.git
fetch = +refs/heads/*:refs/remotes/origin/*
The line you see commented out is an alternative address for the repository that I sometimes switch to simply by changing which line is commented out.
This is the file that is getting manipulated under-the-hood when you run something like git remote rm
or git remote add
but in this case since its only a typo you made it might make sense to correct it this way.