printf template function broken in v1.3.0 custom executors

[jeanschmitt]

Hello,

Using printf template function in custom executors doesn't work since v1.3.0 update.

Here is a minimal reproductible example:

# lib/custom_executor.yaml
executor: custom_executor
steps:
  - type: exec
    script: echo '{{ .testvar }}'
    vars:
      out1:
        from: result.systemout
  - type: exec
    script: echo '{{ printf "%s" .testvar }}'
    vars:
      out2:
        from: result.systemout
output:
  out1: "{{ .out1 }}"
  out2: "{{ .out2 }}"

# suite.yaml
vars:
  testvar: "hello"
testcases:
  - name: direct
    steps:
      - type: exec
        script: echo '{{ printf "%s" .testvar }}'
        assertions:
          - result.systemout ShouldEqual hello
  - name: cust
    steps:
      - type: custom_executor
        assertions:
          - result.out1 ShouldEqual hello
          - result.out2 ShouldEqual hello

venom run --lib-dir=lib suite.yaml

In v1.2.0, the suite runs successfully.

In v1.3.0, we get the following error:

Testcase "cust", step #1-0: Assertion "result.out2 ShouldEqual hello" failed. expected: hello  got: %!s(<nil>) (suite.yaml:0)