Pipenv must not add dependencies if it doesnt exist

[usta]

Hello everyone,

Current workflow of pip have an issue for example :

for example if you want to add pytest as dependency but you make a typo and forget e
pipenv install pytst
because of there isnt any package named pytst but Pipenv still adds it to Pipfile

Issue description

cat PipFile will still show that pytst added to Pipfile

Expected result

it must be added to Pipfile after checking that package exists

[frostming]

Duplicate of #3318