Add -R to coast example

[maxrjones]

Description of proposed changes

The coast example in the docs did not work as written. This PR adds -R to the example.

Fixes #

Reminders

• Make sure that your code follows our style. Use the other functions/files as a basis.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Describe changes to function behavior and arguments in a comment below the function declaration.
• If adding new functionality, add a detailed description to the documentation and/or an example.

[seisman]

Isn't it a bug?

[maxrjones]

Isn't it a bug?

This was not clear to me. I skimmed the docs and did not see any mention of an automatic -R determination happening here except when -M is used as well:

If -M is used with -E then -R or the +r modifier to -E are not required as we automatically determine the region given the selected geographic entities.

This quote from -M mentions a +r modifier to -E, but there's no +r modifier documented for -E.

[PaulWessel]

This feature evolved from just -E to being applicable in -R, so I think some man pages may have obsolete language. That +r modifier is no longer relevant since -R sets region.
However, I think @seisman is right to consider it a bug. We have the -R available via those codes set with -E so we should not have to split it with -R. I am flagging it as a bug.

[seisman]

Actually, the old command without -R works well for me:

gmt coast -JM6i -Baf -EGB,IT,FR+gblue+p0.25p,red -EES,PT,GR+gyellow -pdf map

EDIT: Sorry, it doesn't.

[maxrjones]

I'm closing this PR and have opened a bug report (#5314) instead.

[joa-quim]

EDIT: Sorry, it doesn't.

It does for me