SBOM generation is missing a few Python packages listed in the requirements.txt file

**What happened**:

SBOM generated for python is missing few packages listed in the requirements.txt file

**What you expected to happen**:

SBOM should list all packages mentioned in the requirements.txt file

**Steps to reproduce the issue**:

1. Create requirements.txt with below content and run the syft scan for generate SBOM.

```
PySocks==1.7.1
coloredlogs>=7.3.1
click>=7.0
verboselogs>=1.7
dateparser>=0.7.0

urllib3==1.26.17
requests==2.25.1
retrying==1.3.3
strk-identity-auth==2.49
nwauto-python-commons==0.1.93
flask==2.0.3

wheel>=0.38.1

nose>=1.0
pytz>=2016.10
pytest==3.0.1
computec>=1.0.169
Werkzeug==2.2.2

```
2. Run the Syft

/usr/local/bin/syft /scratch/app/gobgovin/jars/python-requirements/ -o syft-json=syft_python_bom_test.json
✔ Indexed file system /scratch/app/gobgovin/jars/python-requirements
✔ Cataloged contents beb33833a4b4aaabf7dde249b8713668b3b495f08e9619455f643cabe6be8c42
├── ✔ Packages [9 packages]
└── ✔ Executables [0 executables]

Identified only 9 packages, 7 packages are missing.
ex : verboselog:1.7, dateparser:0.7.0, etc (These are some of missing packages to identify by sfyt)

**Anything else we need to know?**:
Syft is parsing only {package-name}**==**{version} format only, remaining all other formats are not parsing and listing in SBOM from requirements.txt . (ex: {package-name}**>=**{version})
Please refer page, few other formats also supported by python requirements.txt file - https://packaging.python.org/en/latest/specifications/version-specifiers/#version-specifiers

**Environment**:
- Output of `syft version`:
Application: syft
Version: 1.4.1
BuildDate: 2024-05-09T19:45:46Z
GitCommit: c200896a9644f9b6bd4bc3785c848276c33bb53c
GitDescription: v1.4.1
Platform: linux/amd64
GoVersion: go1.21.9
Compiler: gc

- OS (e.g: `cat /etc/os-release` or similar):
NAME="Oracle Linux Server"
VERSION="7.9"