Invalid variables in left hand of JEXL or expression are not evaluated

[jaredlockhart]

While working on #7440 I noticed that the left hand operands of an || expression in JEXL are not evaluated in either the Rust or JS implementations, see below:

In Rust:

(Pdb) targetting_helper.eval_jexl('asdf || true')
True
(Pdb) targetting_helper.eval_jexl('asdf || false')
False
(Pdb) targetting_helper.eval_jexl('true || asdf')
True
(Pdb) targetting_helper.eval_jexl('false || asdf')
*** nimbus_rust.NimbusError.EvaluationError: EvaluationError: Identifier 'asdf' is undefined

In JS:

await targetingContext.evalWithDefault('asdf || true');
true
await targetingContext.evalWithDefault('asdf || false');
false
await targetingContext.evalWithDefault('true || asdf');
true
await targetingContext.evalWithDefault('false || asdf');
null

This means that if someone includes an invalid variable in their JEXL expression it will not be caught by the integration tests. In theory we could make changes to both the JS and Rust implementations of the JEXL evaluator to change this behaviour, but in the mean time we can account for this by tokenizing the expression and evaluating them each individually in addition to the entire expression.

Let's update both the desktop and sdk integration tests to account for this.

┆Issue is synchronized with this Jira Task