captureStdoutStderr*: move to Hydra::Helper::Exec which helps avoid some environment variable fixation problems

src/lib/Hydra/Plugin/BazaarInput.pm

@@ -5,6 +5,7 @@ use warnings;
 use parent 'Hydra::Plugin';
 use Digest::SHA qw(sha256_hex);
 use File::Path;
+use Hydra::Helper::Exec;
 use Hydra::Helper::Nix;
 use Nix::Store;
 

src/lib/Hydra/Plugin/DarcsInput.pm

@@ -5,6 +5,7 @@ use warnings;
 use parent 'Hydra::Plugin';
 use Digest::SHA qw(sha256_hex);
 use File::Path;
+use Hydra::Helper::Exec;
 use Hydra::Helper::Nix;
 use Nix::Store;
 

src/lib/Hydra/Plugin/MercurialInput.pm

@@ -6,6 +6,7 @@ use parent 'Hydra::Plugin';
 use Digest::SHA qw(sha256_hex);
 use File::Path;
 use Hydra::Helper::Nix;
+use Hydra::Helper::Exec;
 use Nix::Store;
 use Fcntl qw(:flock);
 

src/lib/Hydra/Plugin/SubversionInput.pm

@@ -4,6 +4,7 @@ use strict;
 use warnings;
 use parent 'Hydra::Plugin';
 use Digest::SHA qw(sha256_hex);
+use Hydra::Helper::Exec;
 use Hydra::Helper::Nix;
 use IPC::Run;
 use Nix::Store;