actions: Stop using Addressee's helpers in recipient_for_emails.
actions: Stop using Addressee's helpers in recipient_for_emails.

recipient_for_emails is used by our typing notifications code.
user_profiles_from_unvalidated_emails is used by our typing
notifications code *and* for sending messages.
user_profiles_from_unvalidated_emails is a part of a larger
framework used by Addressee to validate recipient emails when sending
messages and will eventually need to be removed as we move forward
with #9474. So it makes sense to just inline this function within
recipient_for_emails so that we don't break our typing notifications
code in the future.

This commit is a part of our efforts surrounding #9474.

jackrzhang/zulip,andersk/zulip,kou/zulip,hackerkid/zulip,timabbott/zulip,jackrzhang/zulip,brainwane/zulip,timabbott/zulip,shubhamdhama/zulip,timabbott/zulip,brainwane/zulip,jackrzhang/zulip,tommyip/zulip,synicalsyntax/zulip,showell/zulip,punchagan/zulip,dhcrzf/zulip,hackerkid/zulip,punchagan/zulip,rht/zulip,rishig/zulip,jackrzhang/zulip,dhcrzf/zulip,kou/zulip,jackrzhang/zulip,jackrzhang/zulip,zulip/zulip,shubhamdhama/zulip,jackrzhang/zulip,eeshangarg/zulip,rht/zulip,brainwane/zulip,rishig/zulip,rht/zulip,kou/zulip,punchagan/zulip,synicalsyntax/zulip,brainwane/zulip,eeshangarg/zulip,tommyip/zulip,andersk/zulip,tommyip/zulip,tommyip/zulip,synicalsyntax/zulip,timabbott/zulip,showell/zulip,brainwane/zulip,andersk/zulip,showell/zulip,rishig/zulip,brainwane/zulip,shubhamdhama/zulip,rht/zulip,tommyip/zulip,showell/zulip,andersk/zulip,zulip/zulip,eeshangarg/zulip,punchagan/zulip,synicalsyntax/zulip,synicalsyntax/zulip,shubhamdhama/zulip,dhcrzf/zulip,synicalsyntax/zulip,timabbott/zulip,punchagan/zulip,eeshangarg/zulip,rishig/zulip,kou/zulip,eeshangarg/zulip,zulip/zulip,synicalsyntax/zulip,zulip/zulip,zulip/zulip,dhcrzf/zulip,rht/zulip,hackerkid/zulip,tommyip/zulip,kou/zulip,showell/zulip,tommyip/zulip,rht/zulip,rishig/zulip,shubhamdhama/zulip,punchagan/zulip,hackerkid/zulip,andersk/zulip,rishig/zulip,eeshangarg/zulip,dhcrzf/zulip,timabbott/zulip,andersk/zulip,punchagan/zulip,rishig/zulip,hackerkid/zulip,zulip/zulip,dhcrzf/zulip,andersk/zulip,showell/zulip,brainwane/zulip,zulip/zulip,shubhamdhama/zulip,eeshangarg/zulip,shubhamdhama/zulip,hackerkid/zulip,kou/zulip,dhcrzf/zulip,kou/zulip,hackerkid/zulip,timabbott/zulip,rht/zulip,showell/zulip