fix: Overlay sccache to work with rust v1.48.0

See issue mozilla/sccache#887 for more details

flake.nix

@@ -135,6 +135,7 @@
           (self.overlay."${system}")
           (import ./nix/overlays/alacritty)
           (import ./nix/overlays/neovim)
+          (import ./nix/overlays/sccache)
           (import inputs.nixpkgs-mozilla)
         ]);
       };

nix/overlays/sccache/default.nix

@@ -0,0 +1,20 @@
+# Overlay current master version until new release is cut
+# see: https://github.com/mozilla/sccache/issues/887
+
+self: super:
+
+let metadata = import ./metadata.nix;
+in {
+  sccache = super.sccache.overrideAttrs (old: rec {
+    version = metadata.version;
+    src = super.fetchFromGitHub {
+      owner = "mozilla";
+      repo = "sccache";
+      rev = metadata.rev;
+      sha256 = metadata.sha256;
+    };
+
+    cargoSha256 = metadata.cargoSha256;
+  });
+}
+

nix/overlays/sccache/metadata.nix

@@ -0,0 +1,11 @@
+{
+  upattr = "sccache";
+  repo_git = "https://github.com/mozilla/sccache";
+  version = "0.2.14-dev";
+  branch = "master";
+  rev = "5c60588e324e3d749c8991b37c76eb7ea82dfd6b";
+
+  sha256 = "19z9fdkn3bnr8q33m66h2by6bs6kmhw3a2lq2n8bywmnhrjwhxpw";
+  cargoSha256 = "sha256-fEiq4yMRk8GNdUiJAaF/NJYRB8JFlx1AE7kQ+xrXaXo=";
+}
+