Fix sizeKey on Image without sizes

src/components/molecules/PhotoCard.svelte

@@ -30,7 +30,7 @@
                 <div class="photo-card__info">
                     <Image
                         id={location.country.flag.id}
-                        sizeKey="square"
+                        sizeKey="square-small"
                         width={24}
                         height={24}
                         alt="Flag of {location.country.name}"

src/components/molecules/PostCard.svelte

@@ -31,7 +31,7 @@
             <Image
                 class="flag"
                 id={flagId}
-                sizeKey="square"
+                sizeKey="square-small"
                 width={32} height={32}
                 alt="Flag of {country}"
             />

src/routes/photos.svelte

@@ -370,7 +370,7 @@
                                 <Image
                                     class="icon"
                                     id={countryFlagId}
-                                    sizeKey="square"
+                                    sizeKey="square-small"
                                     width={26} height={26}
                                     alt="{filterCountry} flag"
                                 />

src/routes/subscribe.svelte

@@ -36,7 +36,7 @@
                     <a href={link} target="_blank" rel="external noreferrer noopener">
                         <Image
                             id={id}
-                            sizeKey="issue-thumbnail"
+                            sizeKey="issue-thumbnail-small"
                             width={160} height={112}
                             alt="Issue {issue} thumbnail"
                         />