fix(step-indicator): ensure 45px bottom margin (#563)

@natalia-fitzgerald requested a consistent 45px spacing between the step
indicator and the content to match the designs, so I've put together
this small change for pre-clearance.

## Changes

- adjusts spacing to ensure 45px spacing between step indicator and the
content below it

## How to test this PR

1. Is the step indicator consistently 45px above the content below it?

## Screenshots
<img width="1904" alt="Screenshot 2024-05-22 at 6 51 03 AM"
src="https://github.com/cfpb/sbl-frontend/assets/19983248/a3dec0c4-9769-4258-b46c-27d1dd943347">

src/components/StepIndicator.tsx

@@ -85,7 +85,7 @@ export function StepIndicator({
 }: StepIndicatorPropertyTypes): JSX.Element {
   return (
     <div className='step-indicator' aria-label='progress'>
-      <div className='my-10 flex w-full flex-1 grow flex-row p-0'>
+      <div className='mt-10 flex w-full flex-1 grow flex-row p-0'>
         {steps.map((step, stepIndex) => (
           <Step key={step.label} {...step} hasMargin={stepIndex > 0} />
         ))}

src/pages/Filing/FilingApp/FilingSteps.tsx

@@ -38,7 +38,7 @@ export function FilingSteps(): JSX.Element {
     <Grid.Wrapper center>
       <Grid.Row>
         {/* TODO: Re-evaluate container and step indicator widths */}
-        <Grid.Column width={12}>
+        <Grid.Column className='u-mb0' width={12}>
           <StepIndicator steps={filingSteps} />
         </Grid.Column>
       </Grid.Row>

src/pages/Filing/FilingApp/FilingSubmit.tsx

@@ -54,7 +54,7 @@ function InstitutionYearLabel({
   year: number | string | undefined;
 }): JSX.Element {
   return (
-    <div className='u-mb15 text-sm font-semibold uppercase tracking-[.063rem]'>
+    <div className='u-mb15 u-mt45 text-sm font-semibold uppercase tracking-[0.0625rem]'>
       {name ?? 'Unknown institution'} | {year ?? '2024'}
     </div>
   );
@@ -121,7 +121,7 @@ export function FilingSubmit(): JSX.Element {
       <FilingSteps />
       <Grid.Wrapper center>
         <Grid.Row>
-          <Grid.Column width={8} className='u-mt15'>
+          <Grid.Column width={8} className='u-mt0'>
             <InstitutionYearLabel name={institution.name} year={year} />
             <TextIntroduction
               heading='Sign and submit'