Bump jpeg-decoder version pin to 0.3.0

The jpeg-decoder project has a new version with a number of improvements
plus a fix for a possible panic.
Semantic versioning considers 0.2.4 to be incompatible with 0.3.X because
of the leading zero, so this change bumps the pin to 0.3.0.

Cargo.toml

@@ -10,7 +10,7 @@ edition = "2018"
 
 [dependencies]
 weezl = "0.1.0"
-jpeg = { package = "jpeg-decoder", version = "0.2.4", default-features = false }
+jpeg = { package = "jpeg-decoder", version = "0.3.0", default-features = false }
 flate2 = "1.0.20"
 
 [dev-dependencies]