Expand the spawn host setup script created in WT-11188 so that users no longer need to configure env variables/setup state when using gdb or the wt util tool.

Some examples of variables to set up are:

• Update LD_LIBRARY_PATH to point at both TCMALLOC_LIB and libwiredtiger.so
• Correctly configure solib-search-path in gdb. On gdb open users no longer need to set this variable. This may be handled by LD_LIBRARY path above
• Fix the substitution-path in gdb so gdb automatically looks in the correct location for source code
• Check that all environment variables are updated so that the wt util tool can be used without out any user configuration of the environment