Update go get flag

to avoid future dependencies issues like this one:
v2fly/domain-list-community#52

.github/workflows/build.yml

@@ -37,7 +37,7 @@ jobs:
 
       - name: Build geoip.dat
         run: |
-          go get -u -v -insecure $REPO_URL
+          go get -v -insecure $REPO_URL
           geoip --country=./geoip/GeoLite2-Country-Locations-en.csv --ipv4=./geoip/GeoLite2-Country-Blocks-IPv4.csv --ipv6=./geoip/GeoLite2-Country-Blocks-IPv6.csv
 
       - name: Generate geoip.dat sha256 checksum