Python cataloging fails to remove some non-version characters from version string

[robcresswell]

1. Create a requirements.txt with the following content:

   argh==0.26.2 \
     --hash=sha256:a9b3aaa1904eeb78e32394cd46c6f37ac0fb4af6dc488daa58971bdc7d7fcaf3 \
     --hash=sha256:e9535b8c84dc9571a48999094fda7f33e63c3f1b74f3e5f3ac0105a58405bb65

2. Run syft requirements.txt. Note the version is 0.26.2 \, where it should be 0.26.2

syft version output:

$ syft version
Application:        syft
Version:            0.62.0
JsonSchemaVersion:  6.0.0
BuildDate:          2022-11-18T19:09:50Z
GitCommit:          da4b2df57640e03f273a2e7e9b04eca40555e139
GitDescription:     v0.62.0
Platform:           darwin/amd64
GoVersion:          go1.18.7
Compiler:           gc