Remove redundant links to ECCO variable lists

Author: andrewdelman

ecco_access/ecco_access_tutorials/ECCO_access_intro.ipynb

@@ -3441,21 +3441,7 @@
    "source": [
     "## What if you don't know the ShortName already?\n",
     "\n",
-    "[NASA Earthdata](https://search.earthdata.nasa.gov/search) datasets are identified by ShortNames, but you might not know the ShortName of the variable or category of variables that you are seeking. One way to find the ShortName is to consult the ECCOv4r4 variable lists:\n",
-    "\n",
-    "[ECCO v4r4 llc90 Grid Dataset Variables - Monthly Means](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_nctiles_monthly_varlist.txt)\n",
-    "\n",
-    "[ECCO v4r4 llc90 Grid Dataset Variables - Daily Means](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_nctiles_daily_varlist.txt)\n",
-    "\n",
-    "[ECCO v4r4 llc90 Grid Dataset Variables - Daily Snapshots](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_nctiles_snapshots_varlist.txt)\n",
-    "\n",
-    "[ECCO v4r4 0.5-Deg Interp Grid Dataset Variables - Monthly Means](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_latlon_monthly_varlist.txt)\n",
-    "\n",
-    "[ECCO v4r4 0.5-Deg Interp Grid Dataset Variables - Daily Means](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_latlon_daily_varlist.txt)\n",
-    "\n",
-    "[ECCO v4r4 Time Series and Grid Parameters](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/varlist/v4r4_tseries_grid_varlist.txt)\n",
-    "\n",
-    "Another option is that you can specify a text string \"query\" in `ecco_access` functions. If \"query\" does not match an existing NASA Earthdata ShortName, it will conduct a case-insensitive search for exact matches of that text string among the variable names and descriptions in the variable lists.\n",
+    "[NASA Earthdata](https://search.earthdata.nasa.gov/search) datasets are identified by ShortNames, but you might not know the ShortName of the variable or category of variables that you are seeking. One way to find the ShortName is to consult the ECCOv4r4 [variable lists](https://ecco-v4-python-tutorial.readthedocs.io/ECCO_access_intro.html#Dataset-ShortNames-and-variables-associated-with-them). Another option is that you can specify a text string \"query\" in `ecco_access` functions. If \"query\" does not match an existing NASA Earthdata ShortName, it will conduct a case-insensitive search for exact matches of that text string among the variable names and descriptions in the variable lists.\n",
     "\n",
     "> Note: if using a \"query\" to search the variable lists, it is recommended to use a single word (or even part of a word) when possible. Since only exact text matches are identified, you are more likely to get results with a shorter query.\n",
     "\n",