doc/man/pytest: fix inline interpreted text without a role

sphinx became stricter when handling interpreted text without a role,
e.g. "`foo`" since [1], see [2]. This results in errors such as:

  sphinx.errors.SphinxError: cannot determine default role!

In the past, heuristics were used to determine how to format the text
(inline code, italic, ..).

Fix another occurrence that should have been marked as inline code
instead.

[1] sphinx-doc/sphinx@114093c
[2] sphinx-doc/sphinx#13904

Signed-off-by: Bastian Krause <bst@pengutronix.de>

Author: Bastian-Krause

doc/man/pytest.rst

@@ -15,7 +15,7 @@ SYNOPSIS
 DESCRIPTION
 -----------
 Labgrid ships a pytest plugin to integrate with the pytest infrastructure. It is
-activated if the `--lg-env` parameter is supplied to the pytest command.
+activated if the ``--lg-env`` parameter is supplied to the pytest command.
 
 The labgrid plugin parses the supplied configuration yaml file as described in
 ``labgrid-device-config``\(5) and allows the usage of the target and environment

man/labgrid-pytest.7

@@ -37,7 +37,7 @@ labgrid-pytest \- labgrid integration for pytest
 .SS DESCRIPTION
 .sp
 Labgrid ships a pytest plugin to integrate with the pytest infrastructure. It is
-activated if the \fI\-\-lg\-env\fP parameter is supplied to the pytest command.
+activated if the \fB\-\-lg\-env\fP parameter is supplied to the pytest command.
 .sp
 The labgrid plugin parses the supplied configuration yaml file as described in
 \fBlabgrid\-device\-config\fP(5) and allows the usage of the target and environment