Fix SQLite amalgamation build on macOS

Author: nhynes

build/BUILD.sqlite3

@@ -283,7 +283,7 @@ genrule(
         # would also construct tclsqlite3.c, but we don't use that
         # file, so we don't bother building it.
         + "&& pushd $(RULEDIR)/build >/dev/null "
-        + "&& tclsh tool/mksqlite3c.tcl "
+        + "&& HOME='' tclsh tool/mksqlite3c.tcl "
         + "&& popd >/dev/null "
 
         # Copy the outputs somewhere that Bazel will find them.