[LSP8] Define if `0x` prefix should be added to `LSP8MetadataBaseURI`

[CJ42]

For LSP8TokenIdFormat 3 or 4 (= bytes32)

Should we construct the final URI like this:

http://mybase.uri/e5fe3851d597a3aa8bbdf8d8289eb9789ca2c34da7a7c3d0a7c442a87b81d5c2

Or like this?

http://mybase.uri/0xe5fe3851d597a3aa8bbdf8d8289eb9789ca2c34da7a7c3d0a7c442a87b81d5c2

Depending on choice, write down the following note in the LSP8 specs under the section LSP8MetadataBaseURI.

Note that for the tokenId format 3 and 4, the 0x prefix of the tokenId MUST / MUST NOT be added in the final constructed URI because

[lykhonis]

Address (2), Hashed (4), and Identifier (3) must have 0x as they are true representation of content. Number (0) and String (1) should not, because they are decimal number and string respectively.