docs: fix broken `make` in `docs/`

We had some wrapped lines without blank lines between, which made the runrst
script think the list was not a list and it got confused about the
indentation. I added blank lines, and also some other minor styling for
consistency with the rest of the file.

mercurial/helptext/config.txt

@@ -3003,17 +3003,22 b' User interface controls.'
     This is used to adjust behavior and performance to best fit the repository purpose.
 
     Currently recognised values are:
-    - default: an all purpose repository
+
+    - ``default``: an all purpose repository
 
 ``resources``
     How aggressive Mercurial can be with resource usage:
 
     Currently recognised values are:
-    - default: the default value currently is equivalent to medium,
-    - high:    allows for higher cpu, memory and disk-space usage to improve
+
+    - ``default``: the default value currently is equivalent to medium,
+
+    - ``high``: allows for higher cpu, memory and disk-space usage to improve
                performance of some operations.
-    - medium:  aims at a moderate resource usage,
-    - low:     reduces resources usage when possible, decreasing overall
+
+    - ``medium``: aims at a moderate resource usage,
+
+    - ``low``: reduces resources usage when possible, decreasing overall
       performance.
 
     For finer configuration, see also `usage.resources.cpu`,
@@ -3023,32 +3028,43 b' User interface controls.'
     How aggressive Mercurial can be in terms of cpu usage:
 
     Currently recognised values are:
-    - default: the default value, inherits the value from `usage.resources`,
-    - high:    allows for more aggressive cpu usage, improving storage quality and
-               the performance of some operations at the expense of machine load
-    - medium:  aims at a moderate cpu usage,
-    - low:     reduces cpu usage when possible, potentially at the expense of
+
+    - ``default``: the default value, inherits the value from `usage.resources`,
+
+    - ``high``: allows for more aggressive cpu usage, improving storage quality
+      and the performance of some operations at the expense of machine load
+
+    - `medium`:  aims at a moderate cpu usage,
+
+    - `low`:  reduces cpu usage when possible, potentially at the expense of
                slower operations, increased storage and exchange payload.
 
 ``resources.disk``
     How aggressive Mercurial can be in terms of disk usage:
 
-    Currently recognised values are:
-    - default: the default value, inherits the value from `usage.resources`,
-    - high:    allows for more disk space usage where it can improve performance,
-    - medium:  aims at a moderate disk usage,
-    - low:     reduces disk usage when possible, decreasing performance in some
+    Currently recognised values are::
+    - ``default``: the default value, inherits the value from `usage.resources`,
+
+    - ``high``: allows for more disk space usage where it can improve performance,
+
+    - ``medium``:  aims at a moderate disk usage,
+
+    - ``low``:  reduces disk usage when possible, decreasing performance in some
                occasion.
 
 ``resources.memory``
     How aggressive Mercurial can be in terms of memory usage:
 
-    Currently recognised values are:
-    - default: the default value, inherits the value from `usage.resources`,
-    - high:    allows for more aggressive memory usage to improve overall
+    Currently recognised values are::
+
+    - ``default``: the default value, inherits the value from `usage.resources`,
+
+    - ``high``: allows for more aggressive memory usage to improve overall
                performance,
-    - medium:  aims at a moderate memory usage,
-    - low:     reduces memory usage when possible at the cost of overall
+
+    - ``medium``:  aims at a moderate memory usage,
+
+    - ``low``: reduces memory usage when possible at the cost of overall
                performance.