fix(lint): Fix linting issues (#487)

This pull request focuses on improving the documentation and readability of the Webex meme bot application by adding docstrings and minor formatting adjustments. Here's a breakdown of the changes:

*   **Docstrings:**
    *   Added module-level docstrings to `app/close.py`, `app/img.py`, and `app/main.py` providing a high-level overview of the purpose of each module.
    *   Added docstrings to classes (`ExitCommand`, `MakeMemeCommand`, `MakeMemeCallback`) describing their role.
    *   Added docstrings to methods within those classes (`__init__`, `pre_execute`, `execute`, `post_execute`) explaining their functionality, arguments, and return values where applicable. The `get_templates` and `format_meme_string` functions in `app/img.py` have been documented as well.
*   **Formatting:**
    *   Added a line break before the return type annotation in function definitions (e.g., `def execute(...) -> Response:`).
    *   Added the disable comment `# pylint: disable=line-too-long` to a line in `app/meme.py` to disable pylint for that line.
    *   Added the disable comment `# pylint: disable=unused-argument` to the `pre_execute`, `execute`, and `post_execute` methods to disable pylint checks about unused arguments. This is because these methods are part of an interface and must have the same signature even if some arguments are unused.
*   **Variable Naming:**
    *   Renamed the `vars` dictionary to `env_vars` in `tests/test_config.py` for better clarity.
*   **Test Update:**
    *   Added a docstring to the `test_config` function in `tests/test_config.py` to explain its functionality.
*   **Imports Update:**
    *   Updated imports in `tests/test_config.py` to disable pylint for wrong-import-position errors using `# pylint: disable=wrong-import-position`.

In essence, these changes enhance the maintainability and understandability of the codebase through comprehensive documentation and minor code style improvements.

Reviewed-on: #487

app/img.py

@@ -1,3 +1,5 @@
+"""Generates meme images using the memegen.link API."""
+
 import requests
 
 CHAR_REPLACEMENTS: list = [
@@ -17,6 +19,11 @@ CHAR_REPLACEMENTS: list = [
 
 
 def get_templates() -> list[dict]:
+    """Fetches available meme templates from the memegen.link API.
+
+    Returns:
+        list[dict]: A list of dictionaries containing meme template information.
+    """
     url: str = "https://api.memegen.link/templates"
     req: requests.Response = requests.get(url=url, timeout=10)
     req.raise_for_status()
@@ -40,6 +47,14 @@ def get_templates() -> list[dict]:
 
 
 def format_meme_string(input_string: str) -> str:
+    """Formats a string for use in a meme image URL.
+
+    Args:
+        input_string (str): The string to format.
+
+    Returns:
+        str: The formatted string suitable for meme image URLs.
+    """
     # https://memegen.link/#special-characters
     out_string: str = input_string
     for char_replacement in CHAR_REPLACEMENTS:
@@ -48,6 +63,16 @@ def format_meme_string(input_string: str) -> str:
 
 
 def generate_api_url(template: str, top_str: str, btm_str: str) -> str:
+    """Generates a meme image URL using the memegen.link API.
+
+    Args:
+        template (str): The template identifier in the format "name.ext".
+        top_str (str): The text for the top line of the meme.
+        btm_str (str): The text for the bottom line of the meme.
+
+    Returns:
+        str: The complete URL for the meme image.
+    """
     tmpl_name: str
     tmpl_ext: str
     tmpl_name, tmpl_ext = template.split(".")
@@ -55,7 +80,5 @@ def generate_api_url(template: str, top_str: str, btm_str: str) -> str:
     top_str = format_meme_string(top_str)
     btm_str = format_meme_string(btm_str)
 
-    url: str = (
-        f"https://api.memegen.link/images/{tmpl_name}/{top_str}/{btm_str}.{tmpl_ext}"
-    )
+    url: str = f"https://api.memegen.link/images/{tmpl_name}/{top_str}/{btm_str}.{tmpl_ext}"
     return url