Cargo.toml: remove extra version constraint for imgref and polling

The imgref and polling dependencies have an API that shouldn't break
without a major version change. Rely solely on the major version number
to tell Cargo which package to use.

Cargo.toml

@@ -11,10 +11,10 @@ fontconfig = "0.9"
 # links to it. Large dependencies should not be duplicated.
 freetype = { version = "0.7", default-features = false }
 futures-util = "0.3"
-imgref = "1.11"
+imgref = "1"
 libc = "0.2"
 memmap2 = "0.9"
-polling = "3.7"
+polling = "3"
 reis = "0.4"
 rgb = "0.8"
 tokio = { version = "1", features = ["macros", "rt"] }