some tests with approved stubs have the wrong error

for example, the testLimitLegacyStubErrorVolume test:
https://github.com/python/mypy/blob/bd530392cdbe444c63cc21820ad7b9748ea9c816/test-data/unit/check-modules.test#L3015-L3018

since certifi is an approved stub, it should instead suggest installing them, like it does here:

>mypy -c "import certifi"
<string>:1: error: Library stubs not installed for "certifi" (or incompatible with Python 3.10)  [import]
<string>:1: note: Hint: "python3 -m pip install types-certifi"
<string>:1: note: (or run "mypy --install-types" to install all missing stub packages)
<string>:1: note: See https://mypy.readthedocs.io/en/stable/running_mypy.html#missing-imports
Found 1 error in 1 file (checked 1 source file)

but for some reason, these tests (and also the playground) don't do that

Start with test-data/unit/check-modules.test around testLimitLegacyStubErrorVolume and compare its expected error with the certifi example in the issue. Read the approved-stub entry in mypy/stubinfo.py and reproduce the behavior with the provided mypy command. Done means approved stubs suggest installing their types package consistently in the affected tests and playground behavior.