tests: do not run benchmarks by default in 'make check'

`make check' is intended primarily for running functional tests.
For the most part, it does not make sense to run benchmarks in the same
test environment as the functional tests.

Change-Id: I79f867fdab295bdbd4c4b3c785dfd7ede520022e
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>

tests/benchmarks/corelib/json/json.pro

@@ -1,6 +1,5 @@
 TARGET = tst_bench_qtbinaryjson
 QT = core testlib
 CONFIG -= app_bundle
-CONFIG += testcase
 
 SOURCES += tst_bench_qtbinaryjson.cpp

tests/benchmarks/corelib/tools/qalgorithms/qalgorithms.pro

@@ -1,4 +1,3 @@
-CONFIG += testcase
 TARGET = tst_qalgorithms
 QT = core testlib
 SOURCES = tst_qalgorithms.cpp