Fix for #133 (#134)

Change `join` function for assembling `command_to_tail`
to prevent that it is removed from the final eval'ed command. This is
necessary for newer BASH versions where this character had to be escaped
in the previous implementation. This version has been verified with
BASH 5.2.2 and 5.0.7.

kubetail

@@ -245,12 +245,23 @@ fi
 
 # Join function that supports a multi-character separator (copied from http://stackoverflow.com/a/23673883/398441)
 function join() {
-	# $1 is return variable name
-	# $2 is sep
-	# $3... are the elements to join
-	local retname=$1 sep=$2 ret=$3
-	shift 3 || shift $(($#))
-	printf -v "$retname" "%s" "$ret${@/#/$sep}"
+	# $1 is sep
+	# $2... are the elements to join
+	local sep="$1"
+	shift
+
+	local F=0
+	for x in "$@"
+	do
+		if [[ F -eq 1 ]]
+			then
+				echo -n "$sep"
+			else
+				F=1
+			fi
+			echo -n "$x"
+	done
+	echo
 }
 
 # Check if pod query contains a comma and we've not specified "regex" explicitly,
@@ -261,7 +272,7 @@ if [[ "${pod}" = *","* ]] && [ ! "${regex}" == 'regex' ]; then
 	IFS=',' read -r -a pods_to_match <<< "${pod}"
 
 	# Join all pod names into a string with ".*|.*" as delimiter
-	join pod ".*|.*" "${pods_to_match[@]}"
+	pod=$(join ".*|.*" "${pods_to_match[@]}")
 
 	# Prepend and initial ".*" and and append the last ".*"
 	pod=".*${pod}.*"
@@ -389,7 +400,7 @@ then
 fi
 
 # Join all log commands into one string separated by " & "
-join command_to_tail " & " "${logs_commands[@]}"
+command_to_tail=$(join " & " "${logs_commands[@]}")
 
 # Aggregate all logs and print to stdout
 # Note that tail +1f doesn't work on some Linux distributions so we use this slightly longer alternative