Remove deprecated built-in functions

[ashutosh-narkar]

Following built-in functions are deprecated: any, all, re_match, net.cidr_overlap, set_diff, cast_array, cast_set, cast_string, cast_boolean, cast_null, cast_object.

When compiler strict mode is enabled, use of deprecated functions is prohibited and will result in an error. As described in https://github.com/open-policy-agent/opa/issues/6271 some of the strict checks will be enabled by default and hence it's a good idea to remove these deprecated functions.

[prashant3286]

Hi @ashutosh-narkar I would like to contribute to this feature-request. can you please assign it to me. I will be completing this feature request within the timeframe that you have proposed.

[ashutosh-narkar]

Thanks for your interest @prashant3286! As @anderseknert mentioned in https://github.com/open-policy-agent/opa/issues/6258, issues tagged 1.0 need some special consideration and hence picking up something from the good first issue list is a good way to get familiarized with OPA. Thanks!