use long options; fix tex stack command

* Use long options for conda install commands
* Fix conda install command for tex stack (missing `--channel`)

Author: justin-f-perez

docs/Language Servers.ipynb

@@ -225,7 +225,7 @@
     "servers; you can get it with:\n",
     "\n",
     "```bash\n",
-    "conda install -c conda-forge nodejs\n",
+    "conda install --yes --channel conda-forge nodejs\n",
     "# or one of the following, as an administrator\n",
     "choco install nodejs            # Windows with Chocolatey\n",
     "sudo apt-get install nodejs     # Debian/Ubuntu\n",
@@ -318,7 +318,7 @@
     "#### Example: Getting a $\\LaTeX$ stack\n",
     "\n",
     "```bash\n",
-    "conda install -y conda-forge tectonic texlab chktex\n",
+    "conda install --yes --channel conda-forge tectonic texlab chktex\n",
     "```\n",
     "\n",
     "This will install:\n",