doc: requirements: Use Sphinx 8.2.x

Since nrfconnect/sdk-zephyr#3504 resolves the
issue described in
nrfconnect@85eb35f,
use 8.2.x from now onwards.

Signed-off-by: Carles Cufi <[email protected]>

Author: carlescufi

doc/requirements.txt

@@ -17,7 +17,7 @@ pykwalify                       # |     |         |        |         |         |
 pytest                          # |     |         |        |         |         |      |   X    |
 recommonmark                    # |     |         |   X    |    X    |         |      |        |
 snowballstemmer<3.0.0           # https://github.com/snowballstem/snowball/issues/229
-sphinx>=8.1,<8.2                # |  X  |    X    |   X    |    X    |    X    |  X   |   X    |
+sphinx<8.3.0                    # |  X  |    X    |   X    |    X    |    X    |  X   |   X    |
 sphinx-autobuild                # |  X  |    X    |   X    |    X    |    X    |  X   |   X    |
 sphinx-copybutton               # |  X  |         |        |         |         |      |   X    |
 sphinx-ncs-theme<1.1            # |  X  |         |        |         |         |      |        |