Feature cleanup (#7182)

Following up on #7180 with some feature cleanup:

- Move the `database` feature from `plugin` to `default`
- Rename the `database` feature to `sqlite`
- Remove `--features=extra` from a lot of scripts etc. 
- No need to specify this, the `extra` feature is now the same as the
default feature set
- Remove the now-redundant 2nd Ubuntu test run

build-all-maclin.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 echo "---------------------------------------------------------------"
-echo "Building nushell (nu) with --features=extra and all the plugins"
+echo "Building nushell (nu) with dataframes and all the plugins"
 echo "---------------------------------------------------------------"
 echo ""
 
@@ -14,7 +14,7 @@ NU_PLUGINS=(
 )
 
 echo "Building nushell"
-cargo build --features=extra
+cargo build --features=dataframe
 for plugin in "${NU_PLUGINS[@]}"
 do
     echo '' && cd crates/$plugin