Remove feat extra and include in default (#12140)

# Description
The intended effect of the `extra` feature has been undermined by
introducing the full builds on our release pages and having more
activity on some of the extra commands.

To simplify the feature matrix let's get rid of it and focus our effort
on truly either refining a command to well-specified behavior or
discarding it entirely from the `nu` binary and moving it into plugins.

## Details
- Remove `--features extra` from CI
- Don't explicitly name `extra` in full build wf
- Remove feature extra from build-help scripts
- Update README in `nu-cmd-extra`
- Remove feature `extra`
- Fix previously dead `format pattern` tests
- Relax signature of `to html`
- Fix/ignore `html::test_no_color_flag`
- Remove dead features from `version`
- Refine `to html` type signature

# User-Facing Changes
The commands that were previously only available when building with
`--features extra` will now be available to everyone. This increases the
number of dependencies slightly but has a limited impact on the overall
binary size.

# Tests + Formatting
Some tests that were left in `nu-command` during cratification were dead
because the feature was not passed to `nu-command` and only to
`nu-cmd-lang` for feature-flag mention in `version`.
Those tests have now been either fixed or ignored in one case.

# After Submitting
There may be places in the documentation where we point to `--features
extra` that will now be moot (apart from the generated command help)

scripts/build-all-maclin.sh

@@ -21,7 +21,7 @@ NU_PLUGINS=(
 echo "Building nushell"
 (
     cd $REPO_ROOT
-    cargo build --features=dataframe,extra --locked
+    cargo build --features=dataframe --locked
 )
 
 for plugin in "${NU_PLUGINS[@]}"

scripts/build-all-windows.cmd

@@ -5,7 +5,7 @@ echo -------------------------------------------------------------------
 echo.
 
 echo Building nushell.exe
-cargo build --features=dataframe,extra --locked
+cargo build --features=dataframe --locked
 echo.
 
 call :build crates\nu_plugin_example nu_plugin_example.exe

scripts/build-all.nu

@@ -13,7 +13,7 @@ def build-nushell [] {
     print '----------------------------'
 
     cd $repo_root
-    cargo build --features=dataframe,extra --locked
+    cargo build --features=dataframe --locked
 }
 
 def build-plugin [] {

scripts/install-all.ps1

@@ -8,7 +8,7 @@ Write-Output ""
 
 Write-Output "Install nushell from local..."
 Write-Output "----------------------------------------------"
-cargo install --force --path . --features=dataframe,extra --locked
+cargo install --force --path . --features=dataframe --locked
 
 $NU_PLUGINS = @(
     'nu_plugin_example',

scripts/install-all.sh

@@ -12,7 +12,7 @@ echo ""
 
 echo "Install nushell from local..."
 echo "----------------------------------------------"
-cargo install --force --path "$REPO_ROOT" --features=dataframe,extra --locked
+cargo install --force --path "$REPO_ROOT" --features=dataframe --locked
 
 NU_PLUGINS=(
     'nu_plugin_inc'