Remove redundant "make install" from pg_upgrade test suite.
Remove redundant "make install" from pg_upgrade test suite.

A top-level "make install" includes pg_upgrade since commit
9fa8b0ee90c44c0f97d16bf65e94322988c94864.  Back-patch to 9.5, where that
commit first appeared.

zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl,zeroae/postgres-xl