Fix issue #829 "Compiler crashes when declaring maps with procedure"

Inits `o->value` in `check_expr_base_internal()` so doesn't accidentally
  use last (the proc lit was being set to that of previous string)
Adds test to "tests/issues" and changes CI to use new "run" shells

tests/issues/test_issue_829.odin

@@ -0,0 +1,33 @@
+// Tests issue #829 https://github.com/odin-lang/Odin/issues/829
+package test_issues
+
+import "core:fmt"
+import "core:testing"
+import tc "tests:common"
+
+/* Original issue #829 example */
+
+env : map[string]proc(a, b : int) -> int = {
+	"+" = proc(a, b : int) -> int {
+		return a + b
+	},
+}
+
+test_orig :: proc() {
+	fmt.println(env["+"](1, 2))
+}
+
+main :: proc() {
+	t := testing.T{}
+
+	test_orig()
+
+	test_orig_ret(&t)
+
+	tc.report(&t)
+}
+
+test_orig_ret :: proc(t: ^testing.T) {
+	r := fmt.tprint(env["+"](1, 2))
+	tc.expect(t, r == "3", fmt.tprintf("%s: \"%s\" != \"3\"\n", #procedure, r))
+}