Quote the readable.id in Unread::Reader::Scopes

[fotos]

This PR fixes the generated SQL when the readable.id is a UUID.

For example when running:

> user.have_read?(book)

the generated SQL is:

  Punter Exists (0.7ms)  SELECT  1 AS one FROM "people" LEFT JOIN "read_marks"
                ON "read_marks".readable_type  = 'Book'
               AND ("read_marks".readable_id   = a4691c66-344f-4ab1-8dd4-16614f6cbb52 OR "read_marks".readable_id IS NULL)
               AND "read_marks".reader_id      = "user"."id"
               AND "read_marks".reader_type    = 'User'
               AND "read_marks".timestamp     >= '2019-08-03 10:43:02.138041' WHERE "people"."type" IN ('User') AND ("read_marks".id IS NULL) AND "people"."id" = $1 LIMIT $2  [["id", "cf7144b0-2814-48d3-ba17-b46a00b46246"], ["LIMIT", 1]]

and it fails with the following error:

ActiveRecord::StatementInvalid: PG::SyntaxError: ERROR:  syntax error at or near "f"
LINE 3: ...    AND ("read_marks".readable_id   = a4691c66-344f-4ab1-8dd...
                                                             ^

Quoting the readable.id fixes the problem. Related to #60.

[coveralls]

Coverage remained the same at 100.0% when pulling 8fde098 on fotos:fix-readable-id-for-uuid into 161a609 on ledermann:master.

[fotos]

@ledermann is there anything else I need to change in this PR (e.g. changelog, tests)?

We'd love to have the fix merged / released upstream instead of forking the gem for this (small) bug.

Would appreciate some feedback. 🙏

[ledermann]

Sorry for the late answer. Before merging your changes I want to have the tests passing. I would like to ask you to rebase the PR against master, because I just made some Travis related fixes.

[fotos]

Great thanks, the tests are passing now! Let me know if there is anything else.

[ledermann]

Merged, thanks for contribution!