[Aikido] AI Fix for Template Injection in GitHub Workflows Action

[aikido-autofix]

This patch mitigates template injection vulnerabilities in GitHub Workflows by replacing direct references with an environment variable.

✅ 2 issues fixed by this PR, including 2 critical 🚨 issues

Issue	Severity	Description
Sast#340719234	🚨 CRITICAL	A GitHub Actions workflow step contains a template expression referencing potentially untrusted GitHub context fields. This may allow malicious input to be injected into shell commands, leading to a potential supply chain attack as tokens of the CI/CD pipeline could be exfiltrated.
Sast#340719293	🚨 CRITICAL	A GitHub Actions workflow step contains a template expression referencing potentially untrusted GitHub context fields. This may allow malicious input to be injected into shell commands, leading to a potential supply chain attack as tokens of the CI/CD pipeline could be exfiltrated.

High confidence: Aikido has a robust set of benchmarks for similar fixes, and they are proven to be effective.