run-command API: rename "env_array" to "env"

Start following-up on the rename mentioned in c7c4bdeccf3 (run-command
API: remove "env" member, always use "env_array", 2021-11-25) of
"env_array" to "env".

The "env_array" name was picked in 19a583dc39e (run-command: add
env_array, an optional argv_array for env, 2014-10-19) because "env"
was taken. Let's not forever keep the oddity of "*_array" for this
"struct strvec", but not for its "args" sibling.

This commit is almost entirely made with a coccinelle rule[1]. The
only manual change here is in run-command.h to rename the struct
member itself and to change "env_array" to "env" in the
CHILD_PROCESS_INIT initializer.

The rest of this is all a result of applying [1]:

 * make contrib/coccinelle/run_command.cocci.patch
 * patch -p1 <contrib/coccinelle/run_command.cocci.patch
 * git add -u

1. cat contrib/coccinelle/run_command.pending.cocci
   @@
   struct child_process E;
   @@
   - E.env_array
   + E.env

   @@
   struct child_process *E;
   @@
   - E->env_array
   + E->env

I've avoided changing any comments and derived variable names here,
that will all be done in the next commit.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/builtin/worktree.c b/builtin/worktree.c
index 8b32cd1..cd62eef 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -301,7 +301,7 @@ static int checkout_worktree(const struct add_opts *opts,
 	strvec_pushl(&cp.args, "reset", "--hard", "--no-recurse-submodules", NULL);
 	if (opts->quiet)
 		strvec_push(&cp.args, "--quiet");
-	strvec_pushv(&cp.env_array, child_env->v);
+	strvec_pushv(&cp.env, child_env->v);
 	return run_command(&cp);
 }
 
@@ -433,7 +433,7 @@ static int add_worktree(const char *path, const char *refname,
 			strvec_push(&cp.args, "--quiet");
 	}
 
-	strvec_pushv(&cp.env_array, child_env.v);
+	strvec_pushv(&cp.env, child_env.v);
 	ret = run_command(&cp);
 	if (ret)
 		goto done;
@@ -989,9 +989,9 @@ static void check_clean_worktree(struct worktree *wt,
 	validate_no_submodules(wt);
 
 	child_process_init(&cp);
-	strvec_pushf(&cp.env_array, "%s=%s/.git",
+	strvec_pushf(&cp.env, "%s=%s/.git",
 		     GIT_DIR_ENVIRONMENT, wt->path);
-	strvec_pushf(&cp.env_array, "%s=%s",
+	strvec_pushf(&cp.env, "%s=%s",
 		     GIT_WORK_TREE_ENVIRONMENT, wt->path);
 	strvec_pushl(&cp.args, "status",
 		     "--porcelain", "--ignore-submodules=none",