Implement hp-remote-branch-pull (#230)

# Exercise Review

## Exercise Discussion

#187 

## Checklist

- [ ] If you require a new remote repository on the `Git-Mastery`
organization, have you [created a
request](https://github.com/git-mastery/exercises/issues/new?template=request_exercise_repository.yaml)
for it?
- [ ] Have you written unit tests using
[`repo-smith`](https://github.com/git-mastery/repo-smith) to validate
the exercise grading scheme?
- [x] Have you tested your changes using the instructions posted?
- [x] Have you verified that this exercise does not already exist or is
not currently in review?
- [ ] Did you introduce a new grading mechanism that should belong to
[`git-autograder`](https://github.com/git-mastery/git-autograder)?
- [ ] Did you introduce a new dependency that should belong to
[`app`](https://github.com/git-mastery/app)?

Author: desmondwong1215

hands_on/remote_branch_pull.py

@@ -0,0 +1,45 @@
+import os
+
+from exercise_utils.file import append_to_file
+from exercise_utils.git import (
+    add, 
+    checkout,
+    clone_repo_with_git, 
+    commit, 
+    push
+)
+from exercise_utils.github_cli import (
+    get_github_username,
+    fork_repo,
+    has_repo,
+    delete_repo,
+)
+
+__requires_git__ = True
+__requires_github__ = True
+
+
+TARGET_REPO = "git-mastery/samplerepo-company"
+FORK_NAME = "gitmastery-samplerepo-company"
+LOCAL_DIR = "samplerepo-company"
+
+
+def download(verbose: bool):
+    username = get_github_username(verbose)
+    full_repo_name = f"{username}/{FORK_NAME}"
+
+    if has_repo(full_repo_name, True, verbose):
+        delete_repo(full_repo_name, verbose)
+
+    fork_repo(TARGET_REPO, FORK_NAME, verbose, False)
+    clone_repo_with_git(f"https://github.com/{full_repo_name}", verbose, LOCAL_DIR)
+
+    os.chdir(LOCAL_DIR)
+
+    checkout("hiring", True, verbose)
+    append_to_file("employees.txt", "Receptionist: Pam\n")
+    add(["employees.txt"], verbose)
+    commit("Add Pam to employees.txt", verbose)
+
+    push("origin", "hiring", verbose)
+