Log Message:
catch2: update to 2.12.1.

## 2.12.1

### Fixes
* Vector matchers now support initializer list literals better

### Improvements
* Added support for `^` (bitwise xor) to `CHECK` and `REQUIRE`

## 2.12.0

### Improvements
* Running tests in random order (`--order rand`) has been reworked significantly \ 
(#1908)
  * Given same seed, all platforms now produce the same order
  * Given same seed, the relative order of tests does not change if you select \ 
only a subset of them
* Vector matchers support custom allocators (#1909)
* `|` and `&` (bitwise or and bitwise and) are now supported in `CHECK` and \ 
`REQUIRE`
  * The resulting type must be convertible to `bool`

### Fixes
* Fixed computation of benchmarking column widths in ConsoleReporter (#1885, #1886)
* Suppressed clang-tidy's `cppcoreguidelines-pro-type-vararg` in assertions (#1901)
  * It was a false positive trigered by the new warning support workaround
* Fixed bug in test specification parser handling of OR'd patterns using \ 
escaping (#1905)

### Miscellaneous
* Worked around IBM XL's codegen bug (#1907)
  * It would emit code for _destructors_ of temporaries in an unevaluated context
* Improved detection of stdlib's support for `std::uncaught_exceptions` (#1911)