Merge branch 'trunk' of github.com:rtfeldman/roc into str-split

compiler/module/src/low_level.rs

@@ -14,6 +14,7 @@ pub enum LowLevel {
     ListRepeat,
     ListReverse,
     ListConcat,
+    ListContains,
     ListAppend,
     ListPrepend,
     ListJoin,

compiler/module/src/symbol.rs

@@ -691,6 +691,7 @@ define_builtins! {
         15 LIST_PREPEND: "prepend"
         16 LIST_JOIN: "join"
         17 LIST_KEEP_IF: "keepIf"
+        18 LIST_CONTAINS: "contains"
     }
     5 RESULT: "Result" => {
         0 RESULT_RESULT: "Result" imported // the Result.Result type alias