feat: upgrade expr to v1.14 for richer language definition

[jessesuen]

Motivation

Updates antonmedv/expr from v1.13 to v1.14 which has a much richer language definition and includes useful helpers such as hasPrefix, max

I think this will really help with simplifying workflows. I also think it will make the WorkflowEventBinding much more useful and reduce the need for argo-events webhook eventsource.

The other problem that this will solve is that our docs constantly refer to the expr project to see how to write expressions. But if we continue to use the old version, users will hit unexpected errors. e.g.:

Non-transient error: failed to evaluate workflow template expression: unable to evaluate expression 'hasPrefix(payload.Key, \"foo\") == true': reflect: call of reflect.Value.Call on zero Value (1:1)\n | hasPrefix(payload.Key, \"foo\") == true\n | ^

In fact, this is how I discovered the new version in the first place (I was confused on why certain functions were unavailable).

[jessesuen]

v1.14:

vs v1.13:

[agilgur5]

Shortly after this PR it looks like the creator/maintainer of expr filed #11608 about these new functions!
(v1.14 was released just 4 days ago; 2 days before this PR)