docs: reorg plugins installation tabs

In order to better document packer plugins installation methods, and
since `packer plugins install' is not really manual, we split in two
sections the "manual installation".

website/content/docs/plugins/install-plugins.mdx

@@ -24,7 +24,7 @@ Choose the tab that corresponds to the type of plugin you want to install. If yo
 - Single-component plugin names have a prefix containing the component type, like `packer-provisioner-` or `packer-builder`.
 
 <Tabs>
-<Tab heading="Packer init (recommended from Packer v1.7.0)">
+<Tab heading="Packer init (recommended with HCL2 templates)">
 
 -> **Note:** Only _multi-component plugin binaries_ -- plugins named
 packer-plugin-\*, like the `packer-plugin-amazon` -- are expected to work with
@@ -198,28 +198,29 @@ Packer will error if you set the `packer-plugin-` prefix in a `source`. This
 will avoid conflicting with other plugins for other tools, like Terraform.
 
 </Tab>
-<Tab heading="manually (multi-component plugin)">
+<Tab heading="Packer plugins install (recommended with legacy JSON templates)">
 
--> The [`packer plugins`](/packer/docs/commands/plugins), available from Packer v1.8.0, command allows 
-you to install plugins without going through `init`. 
+-> The [`packer plugins`](/packer/docs/commands/plugins), available from Packer v1.8.0, command allows
+you to install plugins without going through `init`.
 
 ```shell
 packer plugins install github.com/hashicorp/vagrant
 ```
 
 ## Plugin Installation Workflow
+
 Plugin installation via `packer plugins install` works similar to that of the `packer init` command, with the following
 exceptions no `required_plugins` block required and can be used with both legacy JSON and HCL2 templates.
 
 * [`packer plugins install`](/packer/docs/commands/plugins) will install plugins in the **last** directory
 in the following numbered list.
 
-1. `PACKER_PLUGINS_PATH` if set will be the sole location for installing plugins. All other 
-plugin directories will be ignored. 
+1. `PACKER_PLUGINS_PATH` if set will be the sole location for installing plugins. All other
+plugin directories will be ignored.
 1. `PACKER_CONFIG_DIR`\plugins on Windows systems, or `PACKER_CONFIG_DIR`/plugins on all other systems.
 
-
-For manual installation of plugin binaries, without the `packer plugins` command, please continue reading.
+</Tab>
+<Tab heading="manually (multi-component plugin)">
 
 The easiest way to manually install a plugin is to name it correctly, then place
 it in the proper directory. To name a plugin correctly, make sure the binary is
@@ -241,7 +242,6 @@ The valid types for plugins are:
 - `provisioner` - A provisioner to install software on images created by a
   builder.
 
-
 </Tab>
 <Tab heading="manually (single-component plugin)">