removed headings-margin-bottom variable

packages/grafana-ui/src/themes/_variables.scss.tmpl.ts

@@ -111,7 +111,6 @@ $font-size-h4: ${theme.typography.heading.h4} !default;
 $font-size-h5: ${theme.typography.heading.h5} !default;
 $font-size-h6: ${theme.typography.heading.h6} !default;
 
-$headings-margin-bottom: ($spacer / 2) !default;
 $headings-font-family: 'Roboto', 'Helvetica Neue', Helvetica, Arial, sans-serif;
 $headings-font-weight: ${theme.typography.weight.normal} !default;
 $headings-line-height: ${theme.typography.lineHeight.s} !default;

public/sass/_variables.generated.scss

@@ -114,7 +114,6 @@ $font-size-h4: 18px !default;
 $font-size-h5: 16px !default;
 $font-size-h6: 14px !default;
 
-$headings-margin-bottom: ($spacer / 2) !default;
 $headings-font-family: 'Roboto', 'Helvetica Neue', Helvetica, Arial, sans-serif;
 $headings-font-weight: 400 !default;
 $headings-line-height: 1.1 !default;

public/sass/base/_type.scss

@@ -109,7 +109,7 @@ h6,
 .h4,
 .h5,
 .h6 {
-  margin-bottom: $headings-margin-bottom;
+  margin-bottom: $space-s;
   font-family: $headings-font-family;
   font-weight: $headings-font-weight;
   line-height: $headings-line-height;