refactor!: extract mason-lspconfig to separate plugin (#109)

The rationale behind this is to make boundaries clearer as mason.nvim
has no direct relation with lspconfig per se.

Also, hopefully, by having it as a separate package like this would
encourage more people to write similar extensions (think mason-dap and
mason-null-ls). Ideally such extensions wouldn't be required at all, but
there are definitely gaps to fill as of today.

From now on you'll need to add `williamboman/mason-lspconfig.nvim` as
a plugin if you want to use the `mason-lspconfig` extension:

```lua
use {
    { "williamboman/mason.nvim", branch = "alpha" },
    "williamboman/mason-lspconfig.nvim",
    "neovim/nvim-lspconfig",
}
```

```lua
Plug "williamboman/mason.nvim", { 'branch': 'alpha' }
Plug "williamboman/mason-lspconfig.nvim"
Plug "neovim/nvim-lspconfig"
```

1 files changed, 0 insertions, 71 deletions

diff --git a/tests/mason-lspconfig/api/command_spec.lua b/tests/mason-lspconfig/api/command_spec.lua
deleted file mode 100644
index 0551c777..00000000
--- a/tests/mason-lspconfig/api/command_spec.lua
+++ /dev/null
@@ -1,71 +0,0 @@
-local spy = require "luassert.spy"
-local stub = require "luassert.stub"
-local match = require "luassert.match"
-
-local server_mappings = require "mason-lspconfig.mappings.server"
-local filetype_mappings = require "mason-lspconfig.mappings.filetype"
-local api = require "mason-lspconfig.api.command"
-local registry = require "mason-registry"
-local Pkg = require "mason-core.package"
-
-describe(":LspInstall", function()
-    server_mappings.lspconfig_to_package["dummylsp"] = "dummy"
-    server_mappings.package_to_lspconfig["dummy"] = "dummylsp"
-    filetype_mappings.dummylang = { "dummylsp" }
-
-    it("should install the provided servers", function()
-        local dummy = registry.get_package "dummy"
-        spy.on(Pkg, "install")
-        api.LspInstall { "dummylsp@1.0.0" }
-        assert.spy(Pkg.install).was_called(1)
-        assert.spy(Pkg.install).was_called_with(match.ref(dummy), {
-            version = "1.0.0",
-        })
-    end)
-
-    it(
-        "should prompt user for server to install based on filetype",
-        async_test(function()
-            local dummy = registry.get_package "dummy"
-            spy.on(Pkg, "install")
-            stub(vim.ui, "select")
-            vim.ui.select.invokes(function(items, opts, callback)
-                callback "dummylsp"
-            end)
-            vim.cmd [[new | setf dummylang]]
-            api.LspInstall {}
-            assert.spy(Pkg.install).was_called(1)
-            assert.spy(Pkg.install).was_called_with(match.ref(dummy), {
-                version = nil,
-            })
-            assert.spy(vim.ui.select).was_called(1)
-            assert.spy(vim.ui.select).was_called_with({ "dummylsp" }, match.is_table(), match.is_function())
-        end)
-    )
-
-    it(
-        "should not prompt user for server to install if no filetype match exists",
-        async_test(function()
-            spy.on(Pkg, "install")
-            stub(vim.ui, "select")
-            vim.cmd [[new | setf nolsplang]]
-            api.LspInstall {}
-            assert.spy(Pkg.install).was_called(0)
-            assert.spy(vim.ui.select).was_called(0)
-        end)
-    )
-end)
-
-describe(":LspUninstall", function()
-    server_mappings.lspconfig_to_package["dummylsp"] = "dummy"
-    server_mappings.package_to_lspconfig["dummy"] = "dummylsp"
-    filetype_mappings.dummylang = { "dummylsp" }
-
-    it("should uninstall the provided servers", function()
-        local dummy = registry.get_package "dummy"
-        spy.on(Pkg, "uninstall")
-        api.LspUninstall { "dummylsp" }
-        assert.spy(Pkg.uninstall).was_called(1)
-        assert.spy(Pkg.uninstall).was_called_with(match.ref(dummy))
-    end)
-end)