Change MSVC compiler setting to /fp:strict

After investigating nonBE from characterization tests, it was discovered that the default MSVC compiler setting of /fp:precise causes cross platform differences.

This setting should actually be /fp:strict to match -ffp-contract=off used for Unix builds.

Testing was performed using P.800-19 which caused the same IVAS_dec_fx binary to produce different results on different systems.

When the binary was recompiled with /fp:strict the output decoded WAV file produced was bitexact across different Windows systems which previously produced different results.

Please note that this means that ideally, this compiler setting should be applied to all binaries used for characterization tests, and this does not explain all differences.