BUG(WS): sendgrid_mailer module does not handle missing files gracefully

[vfedotovs]

❯ python3.11 ./sendgrid_mailer.py
2024-09-06 18:04:19,269 [INFO ] : sendgrid_mailer_main: 88: --- Started sendgrid_mailer module ---
2024-09-06 18:04:19,270 [INFO ] : sendgrid_mailer_main: 89: Trying to open email_body_txt_m4.txt for email body content
2024-09-06 18:04:19,270 [ERROR] : sendgrid_mailer_main: 100: FileNotFoundError: email_body_txt_m4.txt not found.
Traceback (most recent call last):
File "/Users/vfedotovs/projects/v155-RC3-dev-20240906/src/ws/app/wsmodules/./sendgrid_mailer.py", line 164, in
sendgrid_mailer_main()
File "/Users/vfedotovs/projects/v155-RC3-dev-20240906/src/ws/app/wsmodules/./sendgrid_mailer.py", line 106, in sendgrid_mailer_main
with open('basic_price_stats.txt') as file_object:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: 'basic_price_stats.txt'