Mostly to avoid listing every internal package in kotlin-stdlib/kotlin-reflect, as in https://github.com/JetBrains/kotlin/blob/acd5b62148d797ffd24c4811d1d663f0c1ae7885/compiler/testData/diagnostics/testsWithUnsignedTypes/conversions/conversionOfSignedToUnsigned.txt#L144
Because PackageViewDescriptor may consist of several package fragments from different modules (see LazyPackageViewDescriptorImpl#fragments), we now filter out fragments from irrelevant modules before rendering them into the .txt
Reverts and fixes 102f0d3
102f0d3