Merge pull request #19 from tofuutils/docs/tofuenv-auto-install

docs: add TOFUENV_AUTO_INSTALL example usage

README.md

@@ -155,10 +155,17 @@ String (Default: true)
 
 Should tofuenv automatically install tofu if the version specified by defaults or a .opentofu-version file is not currently installed.
 
+Example: if auto installation is enabled, the version will be installed.
 ```console
 TOFUENV_AUTO_INSTALL=true tofu use <version that is not yet installed>
 ```
 
+Example: use 1.6.0-beta3 version that is not installed, and auto installation is disabled.
+```console
+$ TOFUENV_AUTO_INSTALL=false tofuenv use 1.6.0-beta3
+No installed versions of opentofu matched '^1.6.0-beta3$'. TOFUENV_AUTO_INSTALL is set to false, so exiting.
+```
+
 ##### `TOFUENV_CURL_OUTPUT`
 
 Integer (Default: 2)