Merge pull request #441 from sobolevn/patch-2

Typos fixed

lib/bats-core/tracing.bash

@@ -120,7 +120,7 @@ bats_trim_filename() {
 bats_debug_trap() {
 	# don't update the trace within library functions or we get backtraces from inside traps
 	if [[ "$1" != $BATS_ROOT/lib/* && "$1" != $BATS_ROOT/libexec/* ]]; then
-		# The last entry in the stack trace is not useful when en error occured:
+		# The last entry in the stack trace is not useful when an error occurred:
 		# It is either duplicated (kinda correct) or has wrong line number (Bash < 4.4)
 		# Therefore we capture the stacktrace but use it only after the next debug
 		# trap fired.