Remove RUSTFLAGS and RUSTDOCFLAGS from CI config as they override .cargo/config.toml settings

Author: dmidem

.github/workflows/ci-basic.yml

@@ -16,9 +16,6 @@ jobs:
       ROCKSDB_LIB_DIR: /usr/lib
       # Use system-installed Snappy library for compression in RocksDB
       SNAPPY_LIB_DIR: /usr/lib/x86_64-linux-gnu
-      # Enable the `nu6` feature in `zcash_protocol`
-      RUSTFLAGS: '--cfg zcash_unstable="nu6"'
-      RUSTDOCFLAGS: '--cfg zcash_unstable="nu6"'
 
     steps:
       - uses: actions/checkout@v4