[compliance] remove opening brace from test oracles

tests/compliance/check-json.i

 /*run.config
  MACRO: SHARE @FRAMAC_SHARE@/compliance
  NOFRAMAC:
-  EXECNOW: LOG json_@PTEST_NAME@_1.txt python3 -m json.tool < @SHARE@/c11_functions.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_1.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_2.txt python3 -m json.tool < @SHARE@/glibc_functions.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_2.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_3.txt python3 -m json.tool < @SHARE@/nonstandard_identifiers.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_3.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_4.txt python3 -m json.tool < @SHARE@/posix_identifiers.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_4.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_5.txt python3 -m json.tool < @SHARE@/compiler_builtins.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_5.txt 2> @DEV_NULL@
-  EXECNOW: LOG json_@PTEST_NAME@_6.txt python3 -m json.tool < @SHARE@/gcc_builtins.json | head -n 2 > @PTEST_RESULT@/json_@PTEST_NAME@_6.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_1.txt python3 -m json.tool < @SHARE@/c11_functions.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_1.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_2.txt python3 -m json.tool < @SHARE@/glibc_functions.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_2.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_3.txt python3 -m json.tool < @SHARE@/nonstandard_identifiers.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_3.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_4.txt python3 -m json.tool < @SHARE@/posix_identifiers.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_4.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_5.txt python3 -m json.tool < @SHARE@/compiler_builtins.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_5.txt 2> @DEV_NULL@
+  EXECNOW: LOG json_@PTEST_NAME@_6.txt python3 -m json.tool < @SHARE@/gcc_builtins.json | head -n 2 | tail -n 1 > @PTEST_RESULT@/json_@PTEST_NAME@_6.txt 2> @DEV_NULL@
   EXECNOW: LOG json_@PTEST_NAME@_7.txt python3 @PTEST_DIR@/sanity-checks.py @SHARE@ > @PTEST_RESULT@/json_@PTEST_NAME@_7.txt 2> @DEV_NULL@
 */

tests/compliance/oracle/json_check-json_1.txt

-{
     "description": "C11 reserved function and macro identifiers",

tests/compliance/oracle/json_check-json_2.txt

-{
     "description": "Function and macro identifiers defined in the GNU C Library",

tests/compliance/oracle/json_check-json_3.txt

-{
     "description": "Non-ISO C, Non-POSIX identifiers known to the Frama-C standard library",

tests/compliance/oracle/json_check-json_4.txt

-{
     "description": "POSIX.1-2008 reserved function identifiers (plus a few legacy POSIX identifiers)",

tests/compliance/oracle/json_check-json_5.txt

-{
     "description": "Compiler builtins supported by Frama-C (for GCC builtins, see gcc_builtins.json)",

tests/compliance/oracle/json_check-json_6.txt

-{
     "description": "GCC builtins supported by Frama-C",