Fix typo when compiling libduckdb as a static library

[tristan957]

Related to #618

[tristan957]

b1c7ba1#diff-76ed074a9305c04054cdebb9e9aad2d818052b07091de1f20cad0bbac34ffb52R31

[tristan957]

FWIW when trying this locally, I get:

gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Werror=vla -Wendif-labels -Wmissing-format-attribute -Wimplicit-fallthrough=3 -Wcast-function-type -Wshadow=compatible-local -Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard -Wno-format-truncation -Wno-stringop-truncation -O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -mtls-dialect=gnu2 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer -DOPENSSL_NO_ENGINE -Wno-declaration-after-statement -fPIC -fvisibility=hidden -shared -o pg_duckdb.so  src/pgduckdb_background_worker.o src/pgduckdb.o src/pgduckdb_ddl.o src/pgduckdb_detoast.o src/pgduckdb_duckdb.o src/pgduckdb_hooks.o src/pgduckdb_metadata_cache.o src/pgduckdb_node.o src/pgduckdb_options.o src/pgduckdb_planner.o src/pgduckdb_ruleutils.o src/pgduckdb_table_am.o src/pgduckdb_types.o src/pgduckdb_utils.o src/pgduckdb_xact.o src/catalog/pgduckdb_catalog.o src/catalog/pgduckdb_schema.o src/catalog/pgduckdb_storage.o src/catalog/pgduckdb_table.o src/catalog/pgduckdb_transaction.o src/catalog/pgduckdb_transaction_manager.o src/pg/error_data.o src/pg/relations.o src/pg/transactions.o src/pg/types.o src/scan/postgres_scan.o src/scan/postgres_table_reader.o src/utility/copy.o src/vendor/pg_explain.o  src/vendor/pg_ruleutils_14.o src/vendor/pg_ruleutils_15.o src/vendor/pg_ruleutils_16.o src/vendor/pg_ruleutils_17.o -L/usr/lib64  -Wl,-z,relro -Wl,--as-needed  -Wl,-z,pack-relative-relocs -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -Wl,--build-id=sha1    -Wl,--as-needed -fvisibility=hidden -Wl,-rpath,/usr/lib64/pgsql/ -lpq -Lthird_party/duckdb/build/release/src -L/usr/lib64/pgsql -lstdc++ -llz4 third_party/duckdb/build/release/libduckdb_bundle.a
/usr/bin/ld: cannot find third_party/duckdb/build/release/libduckdb_bundle.a: No such file or directory

I don't know how the CI is not hitting this. That static library indeed doesn't exist on my machine.