pgsql: Test most StaticAssert macros in C++ extensions

Test most StaticAssert macros in C++ extensions

Most of the StaticAssert macros already worked in C++ with Clang and
GCC:(the only compilers we're currently testing C++ extension support
for). This adds a regression test for them in our test C++ extension,
so we can safely change their implementation without accidentally
breaking C++.

The only macros that StaticAssert macros that don't work yet are the
StaticAssertVariableIsOfType and StaticAssertVariableIsOfTypeMacro.
These will be added in a follow-on commit.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: /messages/by-id/CAGECzQR21OnnKiZO_1rLWO0-16kg1JBxnVq-wymYW0-_1cUNtg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/451650eaacd5e482380f2b0e506fc81f5aa92fc7

Modified Files
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src/test/modules/test_cplusplusext/test_cplusplusext.cpp | 5 +++++
1 file changed, 5 insertions(+)