GH-49552: [C++][FlightRPC][ODBC] Enable ODBC test build on Linux (#49668)

### Rationale for this change
The test suite needs to be updated so it will build on Linux in addition to Windows & Mac.
Resolves #49552

### What changes are included in this PR?
Miscellaneous changes to get the tests building on Linux.

### Are these changes tested?
Yes.

### Are there any user-facing changes?
No.
* GitHub Issue: #49552

Authored-by: justing-bq <62349012+justing-bq@users.noreply.github.com>
Signed-off-by: Sutou Kouhei <kou@clear-code.com>

Author: justing-bq

ci/scripts/cpp_test.sh

@@ -55,6 +55,7 @@ if ! type minio >/dev/null 2>&1; then
 fi
 case "$(uname)" in
   Linux)
+    exclude_tests+=("arrow-flight-sql-odbc-test")
     n_jobs=$(nproc)
     ;;
   Darwin)

cpp/src/arrow/flight/sql/odbc/CMakeLists.txt

@@ -29,10 +29,7 @@ endif()
 
 add_subdirectory(odbc_impl)
 if(ARROW_BUILD_TESTS)
-  if(WIN32 OR APPLE)
-    # GH-49552 TODO: Enable Linux test build
-    add_subdirectory(tests)
-  endif()
+  add_subdirectory(tests)
 endif()
 
 arrow_install_all_headers("arrow/flight/sql/odbc")