Docs: Updates to User Manual to correct word usage and typos

PiperOrigin-RevId: 357256297

site/docs/user-manual.html

@@ -876,7 +876,7 @@ <h3 id='strategy-options'>Execution strategy</h3>
   These options affect how Bazel will execute the build.
   They should not have any significant effect on the output files
   generated by the build. Typically their main effect is on the
-  speed on the build.
+  speed of the build.
 </p>
 
 <h4 id='flag--spawn_strategy'><code class='flag'>--spawn_strategy <var>strategy</var></code></h4>
@@ -1055,7 +1055,7 @@ <h4 id='flag--keep_going'><code class='flag'>--[no]keep_going</code>  (-k)</h4>
 </p>
 <p>
   While this option is usually associated with the execution phase of
-  a build, it also effects the analysis phase: if several targets are
+  a build, it also affects the analysis phase: if several targets are
   specified in a build command, but only some of them can be
   successfully analyzed, the build will stop with an error
   unless <code class='flag'>--keep_going</code> is specified, in which case the