fixed an typo that will cause a connection issue

it should be https instead of http

Author: dplotnikov

sharepoint/sharepoint-ps/sharepoint-online/Connect-SPOService.md

@@ -55,7 +55,7 @@ Example 1 shows how a SharePoint Online global administrator with credential adm
 $username = "[email protected]"
 $password = "password"
 $cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist $userName, $(convertto-securestring $Password -asplaintext -force)
-Connect-SPOService -Url http://contoso-admin.sharepoint.com/ -Credential $cred
+Connect-SPOService -Url https://contoso-admin.sharepoint.com/ -Credential $cred
 ```
 Example 2 shows how a SharePoint Online global administrator with a username and password connects to a SharePoint Online Administration Center that has the URL http://contoso-admin.sharepoint.com/.