Use /bin/sh when a basic shell is needed

We do not always need a full-features bash, plain sh is enougth for some
scripts.

Author: smortex

spec/octocatalog-diff/fixtures/configs/trivial-enc.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 # The simplest and least functional ENC you'll ever see
 echo '---'

spec/octocatalog-diff/fixtures/repos/default/config/enc.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 # The simplest and least functional ENC you'll ever see
 echo '---'

spec/octocatalog-diff/tests/catalog/computed_spec.rb

@@ -184,7 +184,7 @@
       context 'with working Puppet version' do
         before(:all) do
           @temp_puppet = Tempfile.new('puppet')
-          @temp_puppet.write "#!/bin/bash\n"
+          @temp_puppet.write "#!/bin/sh\n"
           @temp_puppet.write "echo '3.8.7'\n"
           @temp_puppet.close
           FileUtils.chmod 0o755, @temp_puppet.path
@@ -212,7 +212,7 @@
       context 'with failing Puppet version' do
         before(:all) do
           @temp_puppet = Tempfile.new('puppet')
-          @temp_puppet.write "#!/bin/bash\n"
+          @temp_puppet.write "#!/bin/sh\n"
           @temp_puppet.write "echo 1>&2 'something failed horribly'\n"
           @temp_puppet.write "exit 1\n"
           @temp_puppet.close