MINOR: [R] Fix typo in installation vignette (#35388)

### Rationale for this change

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### Are these changes tested?

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Authored-by: Toby Dylan Hocking <toby.hocking@r-project.org>
Signed-off-by: Nic Crane <thisisnic@gmail.com>

r/vignettes/install_nightly.Rmd

@@ -52,4 +52,4 @@ variables for options for configuring the build source and enabled features.
 ## Further reading
 
 - For users looking for information about installing on Linux, see the [Linux installation article](./install.html).
-- For developers looking to understand the installation scripts, see the [instalation details article](./developers/install_details.html). 
+- For developers looking to understand the installation scripts, see the [installation details article](./developers/install_details.html).