boolean, sizeofstring: update after talking with x/tools folks

boolean/boolean_test.go

@@ -0,0 +1,14 @@
+// boolean_test.go
+package bocchi_test
+
+import "git.sunturtle.xyz/zephyr/errors-my-beloved/boolean/challenge"
+
+var _ = map[bool]struct{}{
+	false:                      {},
+	challenge.Flag == "gc25{}": {}, // ERROR: ./boolean_test.go:7:2: duplicate key false in map literal
+}
+
+var _ = map[bool]struct{}{
+	false:                          {},
+	challenge.Flag[13:] != "CRDy}": {}, // silently succeeds, even though it evaluates to false
+}