`fail_if` tag for roles and scripts.

[TarantoolBot]

If the tag fail_if is set to an expression string role/script
loading will raise an error, if fail_if expression is evaluated
to be true.

The syntax for fail_if tag is the same as in config conditional.if
section.

Example:

-- --- #tarantool.metadata.v1
-- fail_if: "tarantool_version < 3.1.0"
-- ...

Requested by @grafin in tarantool/tarantool@fbaaa14.

[Totktonada]

NB: The version expression syntax is described in https://www.tarantool.io/en/doc/latest/platform/configuration/#conditional-configuration-sections