docs/learning: Remove duplicates

Signed-off-by: Alisa-Dariana Roman <alisa.roman@analog.com>

Author: romandariana

docs/learning/index.rst

@@ -10,7 +10,6 @@ Mixed Signal Basics
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 .. toctree::
-   :caption: Precision ADC Tutorial
    :maxdepth: 1
 
    tutorial_prec_adc/index
@@ -20,31 +19,26 @@ System Design
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 .. toctree::
-   :caption: Converter Connectivity Tutorial (IIO 101)
    :maxdepth: 1
 
    converter_connectivity_tutorial/index
 
 .. toctree::
-   :caption: ADI’s Software Infrastructure for designing with ADCs, DACs, and Sensors
    :maxdepth: 1
 
    sw_infrastructure/index
 
 .. toctree::
-   :caption: Tools for Low Speed Mixed Signal System Design
    :maxdepth: 1
 
    tools_for_ls/index
 
 .. toctree::
-   :caption: Tools for Precision Wideband Mixed Signal System Design
    :maxdepth: 1
 
    tools_for_prec_wb/index
 
 .. toctree::
-   :caption: Tools for High Speed Mixed Signal System Design
    :maxdepth: 1
 
    tools_for_hs/index
@@ -60,11 +54,11 @@ Workshops
 
 
 .. toctree::
-   :caption: A Precision Converter FPGA Integration Journey
    :maxdepth: 1
 
    workshop_a_precision_converter_fpga_integration_journey/index
 
+
 Academic Workshops
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