Minor: remove duplicated lines

[alamirault]

I searched for duplicated lines ^(.*)(\r?\n\1)+$ and found these "issues"

This add more consistency and avoid copy/paste extra blank line

[OskarStark]

You could also switch max blank lines to 1

[OskarStark]

Oh yes...

[alamirault]

@OskarStark

With 1, this file is invalid. As is an expected output, we should exclude violation or remove this line ? Or don't change rule ?

symfony-docs/contributing/code/stack_trace.rst

Lines 123 to 126 in 7a6096e

	$ php bin/console debug:exception
	Command "debug:exception" is not defined.

[OskarStark]

Lets keep it as is, we don't need to be too strict, one and two lines is ok

[javiereguiluz]

This kind of changes might look unexciting ... but I love them because it makes the source of our docs look better ... and I think we should care about the internals as much as about the externals. Thanks Antoine!

[javiereguiluz]

When upmerging there were a ton of conflicts...

... and now I see this when merging from 6.4 to 7.0: 847493b#diff-278a8e1908e2f0de9f2753d344b248e41eebde795a8e340569d2d0a3514cb29e

Is that a merge error?

[alamirault]

When upmerging there were a ton of conflicts...

I'm sorry to hear that :/

secret section is already documented in this page (with better explanation btw), so we can remove this new section. I will do it on the 7.0 PR if is not done before