fix: accept []string and []int in matrix refs (#2956)

Co-authored-by: no-hup <shauryaj.finance@gmail.com>

testdata/for/cmds/Taskfile.yml

@@ -4,6 +4,7 @@ vars:
   OS_VAR: ["windows", "linux", "darwin"]
   ARCH_VAR: ["amd64", "arm64"]
   NOT_A_LIST: "not a list"
+  OS_CSV: "windows,linux,darwin"
 
 tasks:
   # Loop over a list of values
@@ -30,6 +31,16 @@ tasks:
               ref: .ARCH_VAR
         cmd: echo "{{.ITEM.OS}}/{{.ITEM.ARCH}}"
 
+  loop-matrix-ref-computed:
+    cmds:
+      - for:
+          matrix:
+            OS:
+              ref: 'splitList "," .OS_CSV'
+            ARCH:
+              ref: .ARCH_VAR
+        cmd: echo "{{.ITEM.OS}}/{{.ITEM.ARCH}}"
+
   loop-matrix-ref-error:
     cmds:
       - for:

testdata/for/cmds/testdata/TestForCmds-loop-matrix-ref-computed.golden

@@ -0,0 +1,6 @@
+windows/amd64
+windows/arm64
+linux/amd64
+linux/arm64
+darwin/amd64
+darwin/arm64