Fix sql escape function for array of strings

[n-pn]

Searching for records with array field contain other array using @> (e.g Post.query("tags @> ?", tags) does not yield any result.

[n-pn]

I think the problem lies in these two functions:

https://github.com/anykeyh/clear/blob/master/src/clear/expression/expression.cr#L127
https://github.com/anykeyh/clear/blob/master/src/clear/expression/expression.cr#L112

array ["a", "b", "c"] will be escaped as '{''a'', ''b'', ''c''}' instead of '{"a", "b", "c"}' (first one is two ' instead of a single ").

[n-pn]

change method def self.safe_literal(x : Enumerable(AvailableLiteral)) body to

{"ARRAY[", x.map { |item| self.safe_literal(item) }.join(", "), "]"}.join

solve the problem for me.