Fix inconsistent commit ordering for git log (#213)

# Exercise Review

## Exercise Discussion

Fix #212 

## 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.md)
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: jovnc

hands_on/branch_delete.py

@@ -1,3 +1,4 @@
+import time
 import os
 
 from exercise_utils.file import create_or_update_file
@@ -30,4 +31,9 @@ def download(verbose: bool):
     commit("Add fantasy.txt", verbose)
 
     checkout("main", False, verbose)
+
+    # Sleep to ensure that the commit timestamps are different to ensure correct git revision graph in git log
+    time.sleep(1)
+
+
     merge_with_message("textbooks", False, "Merge branch textbooks", verbose)

hands_on/branch_rename.py

@@ -1,3 +1,4 @@
+import time
 import os
 
 from exercise_utils.file import create_or_update_file
@@ -43,4 +44,8 @@ def download(verbose: bool):
     commit("Add fantasy.txt", verbose)
 
     checkout("main", False, verbose)
+
+    # Sleep to ensure that the commit timestamps are different to ensure correct git revision graph in git log
+    time.sleep(1)
+    
     merge_with_message("textbooks", False, "Merge branch textbooks", verbose)

hands_on/early_branch.py

@@ -1,3 +1,4 @@
+import time
 import os
 
 from exercise_utils.file import create_or_update_file, append_to_file
@@ -62,4 +63,8 @@ def download(verbose: bool):
     checkout("main", False, verbose)
     append_to_file("tennis.txt", "Martina Navratilova")
     add(["tennis.txt"], verbose)
+
+    # Sleep to ensure that the commit timestamps are different to ensure correct git revision graph in git log
+    time.sleep(1)
+    
     commit("Add Martina to tennis.txt", verbose)