Environment Variables need to be expanded before checking if valid option in component inputs
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## Problem
When a user defines an input with options, e.g.:
```yaml
spec:
inputs:
a:
options:
- foo
- bar
```
and when setting it to the value of a variable, e.g.:
```yaml
include:
- component: ...
inputs:
a: $VALUE_OF_A
```
it fails because the literal value `$VALUE_OF_A` is not a valid option - that is, neither `foo` nor `bar`.
Even if `VALUE_OF_A=foo`.
issue