sudoers builds shared even if static is specified

[OllieGitHub]

Sudo: 1.9.5p2
Autoconf: 2.69

Issue:
Configuring with "--enable-static-sudoers" still results in sudoers.so

Reason:
SUDOERS_LDFLAGS is not populated correctly because of missing quotes for variable assignment in configure as a result of cb7e82a. This results in SUDOERS_LDFLAGS being empty, as can be seen in config.log
configure:26606: : SUDOERS_LDFLAGS="$SUDOERS_LDFLAGS"
SUDOERS_LDFLAGS=''

SUDOERS_LDFLAGS=--tag=disable-shared -static

Fix
SUDOERS_LDFLAGS="--tag=disable-shared -static"
https://github.com/sudo-project/sudo/blob/master/configure#L27486
https://github.com/sudo-project/sudo/blob/master/configure#L27532