Printing array in matcher

**Description**
I have a matcher to check the contents of a byte array.
In the matcher's "describe" method, the output is preceded by the value under test.
In case of an array, this points to the memory address which off course I'm not interested in.
It would be better to also be able to print the value under test.

**Additional context**
currently this is the kind of output I get:
```
src/test_FC01.cpp:46: PASSED:
REQUIRE_THAT(request.data(), EqualsByteArray(validMessage, 8))
with expansion:
0x000055b38ada8300 equals 0x1101001300250E84
```