Googletest export

Use absl::StrCat in MATCHER_P example for consistency with https://abseil.io/tips/3

PiperOrigin-RevId: 336878481

googlemock/docs/cheat_sheet.md

@@ -498,7 +498,7 @@ which must be a permanent callback.
 | :----------------------------------- | :------------------------------------ |
 | `MATCHER(IsEven, "") { return (arg % 2) == 0; }` | Defines a matcher `IsEven()` to match an even number. |
 | `MATCHER_P(IsDivisibleBy, n, "") { *result_listener << "where the remainder is " << (arg % n); return (arg % n) == 0; }` | Defines a matcher `IsDivisibleBy(n)` to match a number divisible by `n`. |
-| `MATCHER_P2(IsBetween, a, b, std::string(negation ? "isn't" : "is") + " between " + PrintToString(a) + " and " + PrintToString(b)) { return a <= arg && arg <= b; }` | Defines a matcher `IsBetween(a, b)` to match a value in the range [`a`, `b`]. |
+| `MATCHER_P2(IsBetween, a, b, absl::StrCat(negation ? "isn't" : "is", " between ", PrintToString(a), " and ", PrintToString(b))) { return a <= arg && arg <= b; }` | Defines a matcher `IsBetween(a, b)` to match a value in the range [`a`, `b`]. |
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 **Notes:**