MDL-65354 core: pretend that 'moodle/course:browse' never existed

As far as the old capability only was added to master and we are
renaming it before release:

- don't need to deprecate the lang string.
- don't need to make any reference to it in the upgrade.txt info

So, basically, pretend it never existed.

lang/en/deprecated.txt

@@ -153,4 +153,3 @@ hidedockpanel,core_block
 undockall,core_block
 undockblock,core_block
 undockitem,core_block
-course:browse,core_role

lang/en/role.php

@@ -495,6 +495,3 @@ $string['privacy:metadata:role_capabilities:tableexplanation'] = 'The capabiliti
 $string['privacy:metadata:role_capabilities:timemodified'] = 'The date when the capability was created or modified.';
 $string['privacy:metadata:role_cohortroles'] = 'Roles to cohort';
 $string['course:togglecompletion'] = 'Manually mark activities as complete';
-
-// Deprecated since Moodle 3.7
-$string['course:browse'] = 'View list of courses where user is not enrolled';