Allow specifying the output file name

Describe the issue Hello, I was looking for a way to change the output filename when using the -o flag.

I can specify the path to save the file, but as per 2500 it appears that the path is only configurable and not the filename itself.

Additional context

The below output demonstrates the issue:

$ checkov -d . -o json --output-file-path ./checkov-keycloak-report.json
[-snip-]
2022-08-10 16:51:48,144 [MainThread  ] [ERROR]
An error occurred while writing json results to file: ./checkov-keycloak-report.json/results_json.json
Traceback (most recent call last):
  File "/usr/local/Cellar/checkov/2.1.60/libexec/lib/python3.10/site-packages/checkov/common/runners/runner_registry.py", line 102, in save_output_to_file
    with open(file_name, 'w') as f:
FileNotFoundError: [Errno 2] No such file or directory: './checkov-keycloak-report.json/results_json.json'

However, If I change --output-file-path . then it creates the file results_json.json. I want to change the filename locally from results_json.json to checkov-keycloak-report.json

[Mikaciu]

Hello,

I’m afraid the redirection does not export the report for the SARIF format

$ checkov --directory . --hard-fail-on MEDIUM --skip-check CKV_DOCKER_2 --output sarif > checkov.sarif
$ tail -n5 checkov.sarif
        File: /docker/Dockerfile:38-38
        Guide: https://docs.bridgecrew.io/docs/ensure-that-a-user-for-the-container-has-been-created


Wrote output in SARIF format to the file 'results.sarif'

[tspearconquest]

My apologies, I haven’t tested it yet, and was reviewing the code on my phone.

I’ll give this a try when I get some time and report back if I see any problems. Otherwise this can stay closed. Thanks!