Derivations using maven are not deterministic

[vrthra]

Issue description

The builds using maven are not deterministic.

Steps to reproduce

$ nix-build -A javaPackages.mavenHello_1_1        
$ /nix/store/7cl08a5r07jppqxx2ml85dik2zvj2699-maven-hello-1.1

$ nix-build -A javaPackages.mavenHello_1_1 --check
checking path(s) ‘/nix/store/7cl08a5r07jppqxx2ml85dik2zvj2699-maven-hello-1.1’
unpacking sources
unpacking source archive /nix/store/p8m5r18sxcg04lgl0bh4clpwb1pdfiky-maven-hello-v1.1-src
...
'./target/maven-hello-1.1.jar' -> '/nix/store/7cl08a5r07jppqxx2ml85dik2zvj2699-maven-hello-1.1/target/maven-hello-1.1.jar'
error: derivation ‘/nix/store/401jjcp4q8rsjbb4jf232d6frii5z905-maven-hello-1.1.drv’ may not be deterministic: output ‘/nix/store/7cl08a5r07jppqxx2ml85dik2zvj2699-maven-hello-1.1’ differs

Technical details

• System: (NixOS: nixos-version, Ubuntu/Fedora: lsb_release -a, ...)

$ nixos-version 
17.03.873.0c041520c3 (Gorilla)

• Nix version: (run nix-env --version)

$ nix-env --version
nix-env (Nix) 1.11.8

• Nixpkgs version: (run nix-instantiate --eval '<nixpkgs>' -A lib.nixpkgsVersion)

$ nix-instantiate --eval '<nixpkgs>' -A lib.nixpkgsVersion
"17.03.873.0c041520c3"

• Sandboxing enabled: (run grep build-use-sandbox /etc/nix/nix.conf)

Yes.