fix: requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-CERTIFI-3164749
- https://snyk.io/vuln/SNYK-PYTHON-CERTIFI-5805047
- https://snyk.io/vuln/SNYK-PYTHON-REQUESTS-5595532
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-1085966
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-1533435
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-5926907
- https://snyk.io/vuln/SNYK-PYTHON-URLLIB3-6002459

requirements.txt

@@ -1,8 +1,8 @@
-certifi==2020.12.5
+certifi==2023.7.22
 chardet==3.0.4
 idna==2.10
 pynetbox==5.1.1
-requests==2.25.1
+requests==2.31.0
 six==1.15.0
-urllib3==1.26.2
+urllib3==1.26.18
 python3-nmap==1.4.9