#1273 Fix array indexing and length handling for sdk ls

Cf. https://sdkman.slack.com/archives/CJTNQA94M/p1706573532033689?thread_ts=1706516271.626039&cid=CJTNQA94M

- Array indexing is wrong, it starts at 1 (not 0) and ends at the
  highest index, not at array length -1. You have both in C or Java,
  but shell is different.
- Executed in bash the `${#versions}` is - for whatever reason -
  restricted to four bits. So the maximum value is 15. If the versions
  array is > 15, you have to use `${#versions[@]}` instead (cf.
  https://linuxhandbook.com/array-length-bash/).

src/main/bash/sdkman-list.sh

@@ -76,7 +76,7 @@ function __sdkman_offline_list() {
 	__sdkman_echo_no_colour "--------------------------------------------------------------------------------"
 
 	local versions=($(echo ${versions_csv//,/ }))
-	for ((i = ${#versions} - 1; i >= 0; i--)); do
+	for ((i = ${#versions[@]}; i > 0; i--)); do
 		if [[ -n "${versions[${i}]}" ]]; then
 			if [[ "${versions[${i}]}" == "$CURRENT" ]]; then
 				__sdkman_echo_no_colour " > ${versions[${i}]}"