Fix syntax error

pyenv.d/install/latest.bash

@@ -1,8 +1,8 @@
 DEFINITION_PREFIX="${DEFINITION%%:*}"
 DEFINITION_TYPE="${DEFINITION_PREFIX%%-*}" # TODO: support non-CPython versions
 if [[ "${DEFINITION}" != "${DEFINITION_PREFIX}" ]]; then
-  DEFINITION_CANDIDATES=\
-    ($(python-build --definitions | \
+  DEFINITION_CANDIDATES=(\
+    $(python-build --definitions | \
       grep -F "${DEFINITION_PREFIX}" | \
       grep "^${DEFINITION_TYPE}" | \
       sed -E -e '/-dev$/d' -e '/-src$/d' -e '/(b|rc)[0-9]+$/d' | \