Fix removed jinja variable in build.script.content

[hadim]

An attempt to fix #1335

See below:

# Working with this PR ✅
build:
  script:
    content:
      - ${{ PYTHON }} --version

# Working with this PR ✅
build:
  script:
    content: ${{ PYTHON }} --version

# Working before this PR ✅
build:
  script:
    - ${{ PYTHON }} --version

# Working before this PR ✅
build:
  script: ${{ PYTHON }} --version

This issue being that the jinja variables are removed from the string. So ${{ PYTHON }} --version becomes --version during the build.

---

Should I add test(s) for this? If yes then where?

[hadim]

Maybe for the record, I found this PR that introduced support for jinja variables in build.script: #894

[hadim]

I was trying to add a few tests for this but when I remove the fix of this PR, the test still passes, so I am confused. It seems like parsing is done correctly in that simple scenario but fails when using rattler-build.

#[cfg(test)]
mod tests {
    use super::*;
    use serde_yaml;

    #[test]
    fn test_script_content_sequence() {
        let script = Script {
            content: ScriptContent::Commands(vec!["${{ PYTHON }} --version".to_string()]),
            interpreter: Some("bash".to_string()),
            ..Default::default()
        };

        let yaml = serde_yaml::to_string(&script).unwrap();

        let expected_yaml = r#"interpreter: bash
content: ${{ PYTHON }} --version
"#;

        assert_eq!(yaml, expected_yaml);

        let parsed_script: Script = serde_yaml::from_str(&expected_yaml).unwrap();
        assert_eq!(parsed_script, script);
    }
}

[hadim]

I finally added more "high-level" tests in the rust-tests crate.