Update simnode script (#590)

* Update simnode script

* Update simnode script

Author: haroldsphinx

.maintain/run_simnode.sh

@@ -18,7 +18,7 @@ VERSIONS_FILES=(
 /home/runner/.cargo/bin/rustup target add wasm32-unknown-unknown --toolchain nightly
 /home/runner/.cargo/bin/cargo build --release -p simnode
 sudo chown -R runner:runner target/release/simnode && sudo chmod +x target/release/simnode
-sudo chown -R runner:runner /tmp/db
+sudo mkdir -p /tmp/db && sudo chown -R runner:runner /tmp/db
 YDATE=$(date -d yesterday +'%m-%d-%Y')
 
 run_simnode() {