Catch2 floating point matchers documentation is outdated

[jmonticelli]

Describe the bug
Looking at the documentation here it appears that the names of the matchers are missing the Matcher suffix.

Expected behavior
I would expect to be able to follow the guide 1:1 and compile successfully.

Reproduction steps
Steps to reproduce the bug.

#include <catch2/matchers/catch_matchers_floating_point.hpp>

// ...

    REQUIRE_THAT(1.0, Catch::Matchers::WithinAbs(1.2, 0.2));
// ...

Fails to compile with version 3.8.0 of Catch2.

Platform information:
Seems irrelevant for this issue

Additional context

REQUIRE_THAT(1.0, Catch::Matchers::WithinAbsMatcher(1.2, 0.2));

compiles just fine