ASM-4325 EM Discovery is failing with Invalid URI error when domain name is passed as an input

[sushilrai]

ASM Core is passing the username in form of 'domain\username' but for EM API we need it in form of 'domain\username'. Updated the username before passing it to the REST endpoint for authentication cookie generation

[sushilrai]

@shariqiqbal1 please test with UI and merge the changes. Working fine on my development test bed with both domain and non-domain user

[gavin-scott]

I sat with @shariqiqbal1 -- this change is not necessary, the code should work as is. The username should be passed in exactly as it was originally entered by the user.