Feat: View + Manage Pipeline (#53)

This MR adds the `.pipeline()` command which opens up the pipeline popup. This popup shows information about the current pipeline and it's jobs, and gives users the ability to re-trigger failed jobs.

README.md

@@ -119,6 +119,17 @@ require("gitlab").setup({
     close = { "<Esc>", "<C-c>" },
     submit = { "<CR>", "<Space>" },
   },
+  pipeline = {
+    created = "",
+    pending = "",
+    preparing = "",
+    scheduled = "",
+    running = "ﰌ",
+    canceled = "ﰸ",
+    skipped = "ﰸ",
+    success = "✓",
+    failed = "",
+  },
 })
 ```
 
@@ -174,6 +185,12 @@ require("gitlab").approve()
 require("gitlab").revoke()
 ```
 
+You can view the status of the pipeline for the current MR. To re-trigger failed jobs in the pipeline manually, use your `settings.popup.perform_action` keybinding:
+
+```lua
+require("gitlab").pipeline()
+```
+
 The `add_reviewer` and `delete_reviewer` commands, as well as the `add_assignee` and `delete_assignee` functions, will let you choose from a list of users who are availble in the current project:
 
 ```lua
@@ -209,6 +226,7 @@ vim.keymap.set("n", "<leader>glaa", gitlab.add_assignee)
 vim.keymap.set("n", "<leader>glad", gitlab.delete_assignee)
 vim.keymap.set("n", "<leader>glra", gitlab.add_reviewer)
 vim.keymap.set("n", "<leader>glrd", gitlab.delete_reviewer)
+vim.keymap.set("n", "<leader>glp", gitlab.pipeline)
 ```
 
 ## Troubleshooting