Temporarily pin json-ld crate to remove unused dependency

A follow-on patch will regenerate Make-managed files.

References:
* https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html#choice-of-commit

Signed-off-by: Alex Nelson <alexander.nelson@nist.gov>

Author: ajnelson-nist

rust/case2geojson/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 [dependencies]
 geojson = "0.24.1"
 iref = "3.2.2"
-json-ld = "0.21.1"
+json-ld = { git = "https://github.com/miterst/json-ld.git", rev = "6b48152595b661ae5ada46747e15f373e698d151" }
 oxigraph = { version = "0.4.1", default-features = false}
 serde_json = "1.0.135"
 static-iref = "3.0.0"