lingucomponent: avoid -Werror=deprecated-copy (GCC trunk towards GCC 9)

...by removing explicitly user-provided functions that do the same as their
implicitly-defined counterparts, but may prevent implicitly declared copy
functions from being defined as non-deleted in the future.  (Even if a dtor was
declared non-inline in an include file, the apparently-used implicitly-defined
copy functions are already inline, so why bother with a non-inline dtor.)

Change-Id: Ib8eea8d4d2088c8a32c5938985ad14e4609a4237
Reviewed-on: https://gerrit.libreoffice.org/58060
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

lingucomponent/source/languageguessing/guess.cxx

@@ -104,8 +104,4 @@ Guess::Guess(const char * guess_str)
     }
 }
 
-Guess::~Guess()
-{
-}
-
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

lingucomponent/source/languageguessing/guess.hxx

@@ -43,8 +43,6 @@ class Guess final {
          */
         Guess(const char * guess_str);
 
-        ~Guess();
-
         const string& GetLanguage() { return language_str;}
         const string& GetCountry() { return country_str;}