update flake, use correct nix dependencies instead of non-default fontkit features

Cargo.lock

@@ -648,7 +648,6 @@ dependencies = [
  "dirs",
  "dwrote",
  "float-ord",
- "freetype",
  "freetype-sys",
  "lazy_static",
  "libc",
@@ -687,16 +686,6 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aa9a19cbb55df58761df49b23516a86d432839add4af60fc256da840f66ed35b"
 
-[[package]]
-name = "freetype"
-version = "0.7.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a440748e063798e4893ceb877151e84acef9bea9a8c6800645cf3f1b3a7806e"
-dependencies = [
- "freetype-sys",
- "libc",
-]
-
 [[package]]
 name = "freetype-sys"
 version = "0.20.1"