Don't add unnecessary extensions to the test INI for AppVeyor

Several extension test suites have already been changed to rely on the
new behavior of `--EXTENSIONS--` section, i.e. to dynamically load
required extensions on demand.  Thus, there is no need to load these
extensions always, which should improve the performance of executing
the tests.

Author: cmb69

appveyor/build_task.bat

@@ -51,7 +51,9 @@ if %errorlevel% neq 0 exit /b 3
 if "%THREAD_SAFE%" equ "0" set ADD_CONF=%ADD_CONF% --disable-zts
 if "%INTRINSICS%" neq "" set ADD_CONF=%ADD_CONF% --enable-native-intrinsics=%INTRINSICS%
 
-set EXT_EXCLUDE_FROM_TEST=snmp,oci8_12c,pdo_oci,pdo_firebird,ldap,imap,ftp
+set EXT_EXCLUDE_FROM_TEST=snmp,oci8_12c,pdo_oci,pdo_firebird,ldap,imap
+rem the following exts are tested via --EXTENSIONS--; update as necessary
+set EXT_EXCLUDE_FROM_TEST=bz2,exif,fileinfo,ffi,ftp,gd,gmp,soap,sodium,sqlite3,tidy,%EXT_EXCLUDE_FROM_TEST%
 if "%OPCACHE%" equ "0" set EXT_EXCLUDE_FROM_TEST=%EXT_EXCLUDE_FROM_TEST%,opcache
 
 set CFLAGS=/W1 /WX