feat: parse templates in collection-type variables (#1526)

* refactor: replacer

* feat: move traverser to deepcopy package

* feat: nested map variable templating

* refactor: ReplaceVar function

* feat: test cases

* fix: TraverseStringsFunc copy value instead of pointer

testdata/vars/any2/Taskfile.yml

@@ -3,6 +3,8 @@ version: '3'
 tasks:
   default:
     - task: map
+    - task: nested-map
+    - task: slice
     - task: ref
     - task: ref-sh
     - task: ref-dep
@@ -19,6 +21,24 @@ tasks:
           VAR:
             ref: MAP
 
+  nested-map:
+    vars:
+      FOO: "foo"
+      nested:
+        map:
+          variables:
+            work: "{{.FOO}}"
+    cmds:
+      - echo {{.nested.variables.work}}
+
+  slice:
+    vars:
+      FOO: "foo"
+      BAR: "bar"
+      slice_variables_work: ["{{.FOO}}","{{.BAR}}"]
+    cmds:
+      - echo {{index .slice_variables_work 0}} {{index .slice_variables_work 1}}
+
   ref:
     vars:
       MAP: