Documentation: ktap: Separate first bullet list items

The first bullet list items are shown in htmldocs output as combined
with previous paragraph due to missing blank line separator. Add it.

Signed-off-by: Bagas Sanjaya <[e-mail]>
Reviewed-by: Randy Dunlap <[e-mail]>
Signed-off-by: Jonathan Corbet <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

Documentation/dev-tools/ktap.rst

···
 aid human debugging.
 
 KTAP output is built from four different types of lines:
+
 - Version lines
 - Plan lines
 - Test case result lines
···
 version of the (K)TAP standard the result is compliant with.
 
 For example:
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 - "KTAP version 1"
 - "TAP version 13"
 - "TAP version 14"
···
 This output defines the following hierarchy:
 
 A single test called "main_test", which fails, and has three subtests:
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 - "example_test_1", which passes, and has one subtest:
 
    - "test_1", which passes, and outputs the diagnostic message "test_1: initializing test_1"