Added note to let users find documentation of default CLI subcommand easier (#2730)

* adding hint in the help page that the `render` command is invoked automatically
for if you call `manim`

* fixing format string

* fixed note for the epilog

* replaced the backticks with the normal (') ones

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* removing the trailing free line in constants.py

* fixing import issue

* adjusted the help-page output note

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: TornaxO7

manim/__main__.py

@@ -29,7 +29,10 @@ def exit_early(ctx, param, value):
     default="render",
     no_args_is_help=True,
     help="Animation engine for explanatory math videos.",
-    epilog="See 'manim <command>' to read about a specific subcommand.\n\n" + EPILOG,
+    epilog="See 'manim <command>' to read about a specific subcommand.\n\n"
+    "Note: the subcommand 'manim render' is called if no other subcommand "
+    "is specified. Run 'manim render --help' if you would like to know what the "
+    f"'-ql' or '-p' flags do, for example.\n\n{EPILOG}",
 )
 @click.option(
     "--version",