Wrong proc-macro error message when prepared files are out of date in offline mode

[Nemo157]

Bug Description

When the prepared files are out of date the error message claims the directory does not exist, not that the specific query is missing from it (also with an explicit SQLX_OFFLINE I don't think it should mention the DATABASE_URL).

error: `DATABASE_URL` must be set, or `cargo sqlx prepare` must have been run and .sqlx must exist, to use query macros

Minimal Reproduction

Edit some whitespace in a query in a project with prepared queries, run SQLX_OFFLINE=true cargo check.

Info

• SQLx version: v0.7.1
• SQLx features enabled: default, chrono, runtime-tokio, postgres
• Database server and version: Postgres
• Operating system: Linux
• rustc --version: rustc 1.74.0-nightly (7d9bce327 2023-09-16)