Add support for custom padding in form column

[MAILPOET-3654]

tests/javascript/form_editor/store/block_to_form_test_data.js

@@ -250,6 +250,16 @@ export const nestedColumns = {
       attributes: {
         width: '200px',
         verticalAlignment: 'center',
+        style: {
+          spacing: {
+            padding: {
+              top: '10px',
+              right: '20px',
+              bottom: '30px',
+              left: '40px',
+            },
+          },
+        },
       },
       innerBlocks: [
         {

tests/javascript/form_editor/store/blocks_to_form_body.spec.js

@@ -572,6 +572,12 @@ describe('Blocks to Form Body', () => {
     const column2 = columns.body[1];
     expect(column1.type).to.be.equal('column');
     expect(column1.params.width).to.be.equal('200px');
+    expect(column1.params.padding).to.be.deep.equal({
+      top: '10px',
+      right: '20px',
+      bottom: '30px',
+      left: '40px',
+    });
     expect(column1.params.vertical_alignment).to.be.equal('center');
     expect(column1.body.length).to.be.equal(2);
     expect(column2.type).to.be.equal('column');

tests/javascript/form_editor/store/form_body_to_blocks.spec.js

@@ -495,6 +495,12 @@ describe('Form Body To Blocks', () => {
     expect(column1.name).to.be.equal('core/column');
     expect(column1.attributes.width).to.be.equal('66.66%');
     expect(column1.attributes.verticalAlignment).to.be.equal('center');
+    expect(column1.attributes.style.spacing.padding).to.be.deep.equal({
+      top: '10px',
+      right: '20px',
+      bottom: '30px',
+      left: '40px',
+    });
     expect(column1.innerBlocks.length).to.be.equal(2);
     const columns11 = column1.innerBlocks[0];
     checkBlockBasics(column1.innerBlocks[1]);

tests/javascript/form_editor/store/form_to_block_test_data.js

@@ -208,6 +208,12 @@ export const nestedColumns = {
       params: {
         width: 66.66,
         vertical_alignment: 'center',
+        padding: {
+          top: '10px',
+          right: '20px',
+          bottom: '30px',
+          left: '40px',
+        },
       },
       body: [
         {