tests: adjust merge tool config in test-largefiles-update.t
Previously, the `ui.merge=internal:fail` configuration was shadowed by the the
`HGMERGE=internal:merge` environment variable. We would like to remove this
usage of `HGMERGE` variable because it is error-prone (eg: this very test). We
start by cleaning up test independently to avoid large churn when the change
happens.
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}