fix: examples/snowflake/requirements.txt to reduce vulnerabilities

The following vulnerabilities are fixed by pinning transitive dependencies:
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3172287
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3314966
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315324
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315328
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315331
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315452
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315972
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3315975
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3316038
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-3316211
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5663682
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5777683
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5813745
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5813746
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5813750
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-5914629
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-6036192
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-6050294
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-6092044
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-6126975
- https://snyk.io/vuln/SNYK-PYTHON-CRYPTOGRAPHY-6210214

examples/snowflake/requirements.txt

@@ -1,4 +1,4 @@
 rgsync
 snowflake-sqlalchemy
 
-cryptography>=3.2 # not directly required, pinned by Snyk to avoid a vulnerability
+cryptography>=42.0.2 # not directly required, pinned by Snyk to avoid a vulnerability