shortcode function outputs multiple anchor tags

You are trying to remove the filter before adding the filter and one more thing you are not adding the correct priority.

remove_filter( 'the_content', 'wpautop' ); //removing before adding without priorities.
add_filter( 'the_content', 'wpautop' , 99) ;
add_filter( 'the_content', 'shortcode_unautop', 100 );

Try remove the filter at the end with same priority when you add.

add_filter( 'the_content', 'wpautop' , 99) ;
add_filter( 'the_content', 'shortcode_unautop', 100 );
remove_filter( 'the_content', 'wpautop', 99); 
remove_filter( 'the_content', 'shortcode_unautop', 100 );