[tests] add non-regression test for macro with % in cpp extra args

also avoid accidental `*/` in FILTER command

tests/syntax/cpp-command.c

 /* run.config*
-   FILTER: sed "s:/[^ ]*/cpp-command\.[^ ]*\.i:TMPDIR/FILE.i:g; s:$PWD/::; s: -m32::"
+   FILTER: sed "s:/[^ ]*[/]cpp-command\.[^ ]*\.i:TMPDIR/FILE.i:g; s:$PWD/::; s: -m32::"
    OPT: -machdep x86_32 -no-autoload-plugins -cpp-frama-c-compliant -cpp-command "echo [\$(basename '%1') \$(basename '%1') \$(basename '%i') \$(basename '%input')] ['%2' '%2' '%o' '%output'] ['%args']"
    OPT: -machdep x86_32 -no-autoload-plugins -cpp-frama-c-compliant -cpp-command "echo %%1 = \$(basename '%1') %%2 = '%2' %%args = '%args'"
    OPT: -machdep x86_32 -no-autoload-plugins -cpp-frama-c-compliant -cpp-command "printf \"%s\n\" \"using \\% has no effect : \$(basename \"\%input\")\""
    OPT: -machdep x86_32 -no-autoload-plugins -cpp-frama-c-compliant -cpp-command "echo %var is not an interpreted placeholder"
    OPT: -machdep x86_32 -no-autoload-plugins -print-cpp-commands
+   OPT: -cpp-extra-args-per-file=@PTEST_FILE@:"-DPF=\\\"cp%02d_3f\\\"" -no-autoload-plugins @PTEST_FILE@ -print
    */
+
+#include <stdio.h>
+void printer(int i, float f) {
+  printf(PF, i, f);
+}
+
+int main() {
+  printer(1, 1.0);
+}

tests/syntax/oracle/cpp-command.5.res.oracle

+[kernel] Parsing tests/syntax/cpp-command.c (with preprocessing)
+/* Generated by Frama-C */
+#include "errno.h"
+#include "stdarg.h"
+#include "stddef.h"
+#include "stdio.h"
+void printer(int i, float f)
+{
+  printf("cp%02d_3f",i,(double)f);
+  return;
+}
+
+int main(void)
+{
+  int __retres;
+  printer(1,(float)1.0);
+  __retres = 0;
+  return __retres;
+}
+
+