Update comparisons page for like & contains (#922)

## What is the goal of this PR?
Update comparisons page for like & contains

## What are the changes implemented in this PR?
Update comparisons page for like & contains

Author: krishnangovindraj

typeql/modules/ROOT/pages/statements/comparisons.adoc

@@ -82,9 +82,7 @@ Thus, the result of comparing it with `PT24H` (24 hours) is indeterminate.
 
 `string` values allow two additional comparison operators.
 
-WARNING: These operators are unimplemented.
-
 `contains` allows for checking if the string on the left-hand side contains the right-hand side string as a substring.
-The `contains` operator is case-insensitive.
+The `contains` operator performs case-insensitive matching by https://www.w3.org/TR/charmod-norm/#definitionCaseFolding[case-folding] unicode strings.
 
-`like` evaluates whether the string on the left-hand side of the operator matches the regular expression string on the right-hand side.
+`like` evaluates whether the string on the left-hand side of the operator matches the regular expression string on the right-hand side. The regular expression must follow the https://docs.rs/regex/latest/regex/#syntax[rust regex syntax].