new: Fix tests under 3.2.57(1)-release

Under Bash 3.2.57(1)-release, `./go test new` was failing with:

```
 ✗ new: tab complete --internal
   (in test file tests/new.bats, line 76)
     `touch "${internal_modules[@]}"' failed
   touch: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/scripts/lib/foo): No such file or directory
 ✗ new: tab complete --public
   (in test file tests/new.bats, line 94)
     `touch "${public_modules[@]}"' failed
   touch: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/lib/xyzzy): No such file or directory
 ✗ new: tab complete --test
   (in test file tests/new.bats, line 112)
     `touch "${test_files[@]}"' failed
   touch: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/tests/frotz.bats): No such file or directory
 ✗ new: tab complete --type
   (in test file tests/new.bats, line 130)
     `touch "${text_files[@]}"' failed
   touch: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/gue/wizard.txt): No such file or directory
```

At first I thought this was the "declare and initialize an array at the
same time" bug from commit b421c73 and
commit c6bf1cf, as the workaround was
the same: declare the array on one line, and initialize it on another.
After thinking it through, however, I realized this bug was different,
since the earlier bug had to do with exported arrays not getting
initialized, and these arrays were `local`. On top of that, it appeared
that the brace expansion was to blame, since `touch` appeared to see
only the final brace expansion value, and that value was wrapped in
parentheses.

To verify this, I added this line before one of the `touch` calls:

  printf 'ARG: %s\n' "${internal_modules[@]}" >&2

which produced:

 ✗ new: tab complete --internal
   (in test file tests/new.bats, line 77)
     `touch "${internal_modules[@]}"' failed
   ARG: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/scripts/lib/foo)
   touch: (/var/folders/dl/0j29q1wd0w715j4gnz5ry_pc0000gn/T/test rootdir/scripts/lib/foo): No such file or directory

After reviewing https://tiswww.case.edu/php/chet/bash/CHANGES, this
appeared to be the most likely culprit:

  This document details the changes between this version,
  bash-4.1-alpha, and the previous version, bash-4.0-release.

  bb. Fixed a bug that caused brace expansion to take place too soon in
      some compound array assignments.

Using the methodology described in the log message for commit
99ab780, I downloaded the Bash 4.0 and
4.1 sources and patches, and confirmed that the bug manifested under
Bash 4.0.44 (the highest patchlevel for 4.0) and did not manifest under
Bash 4.1.

Also, for future reference, the official Bash git repository is at:

  https://savannah.gnu.org/git/?group=bash
  http://git.savannah.gnu.org/cgit/bash.git

However, neither the patches from
https://mirrors.ocf.berkeley.edu/gnu/bash/ nor the Git repository show a
specific change for the fix, and the diff between 4.0.44 and 4.1 is too
large and difficult to parse to easily identify the fix.

Author: mbland

tests/new.bats

@@ -84,7 +84,8 @@ assert_command_script_is_executable() {
   run "$TEST_GO_SCRIPT" complete 1 new '--i'
   assert_success '--internal '
 
-  local internal_modules=("$TEST_GO_SCRIPTS_DIR/lib/"{bar,baz,foo})
+  local internal_modules
+  internal_modules=("$TEST_GO_SCRIPTS_DIR/lib/"{bar,baz,foo})
   mkdir -p "$TEST_GO_SCRIPTS_DIR/lib/"
   touch "${internal_modules[@]}"
 
@@ -102,7 +103,8 @@ assert_command_script_is_executable() {
   run "$TEST_GO_SCRIPT" complete 1 new '--p'
   assert_success '--public '
 
-  local public_modules=("$TEST_GO_ROOTDIR/lib/"{plugh,quux,xyzzy})
+  local public_modules
+  public_modules=("$TEST_GO_ROOTDIR/lib/"{plugh,quux,xyzzy})
   mkdir -p "$TEST_GO_ROOTDIR/lib/"
   touch "${public_modules[@]}"
 
@@ -120,7 +122,8 @@ assert_command_script_is_executable() {
   run "$TEST_GO_SCRIPT" complete 1 new '--te'
   assert_success '--test '
 
-  local test_files=("$TEST_GO_ROOTDIR/tests/"{aimfiz,blorple,frotz}.bats)
+  local test_files
+  test_files=("$TEST_GO_ROOTDIR/tests/"{aimfiz,blorple,frotz}.bats)
   mkdir -p "$TEST_GO_ROOTDIR/tests/"
   touch "${test_files[@]}"
 
@@ -138,7 +141,8 @@ assert_command_script_is_executable() {
   run "$TEST_GO_SCRIPT" complete 1 new '--ty'
   assert_success '--type '
 
-  local text_files=("$TEST_GO_ROOTDIR/gue/"{dungeonmaster,thief,wizard}.txt)
+  local text_files
+  text_files=("$TEST_GO_ROOTDIR/gue/"{dungeonmaster,thief,wizard}.txt)
   mkdir -p "$TEST_GO_ROOTDIR/gue"
   touch "${text_files[@]}"