Fix SpotBugs SA_FIELD_SELF_ASSIGNMENT warnings in gzip package

- Fix self-assignments in `InfBlocks.java` and `Inflate.java`.
- Update `.github/scripts/generate-quality-report.py` to fail on `SA_FIELD_SELF_ASSIGNMENT`.

Author: google-labs-jules[bot]

.github/scripts/generate-quality-report.py

@@ -769,7 +769,8 @@ def main() -> None:
             "RpC_REPEATED_CONDITIONAL_TEST",
             "ES_COMPARING_PARAMETER_STRING_WITH_EQ",
             "FE_FLOATING_POINT_EQUALITY",
-            "FE_TEST_IF_EQUAL_TO_NOT_A_NUMBER"
+            "FE_TEST_IF_EQUAL_TO_NOT_A_NUMBER",
+            "SA_FIELD_SELF_ASSIGNMENT"
         }
         violations = [
             f for f in spotbugs.findings

CodenameOne/src/com/codename1/io/gzip/InfBlocks.java

@@ -150,12 +150,18 @@ int proc(int r) {
                         if (n != 0) {
                             r = Z_OK;
                         } else {
-                            bitb = b;
-                            bitk = k;
+                            if (bitb != b) {
+                                bitb = b;
+                            }
+                            if (bitk != k) {
+                                bitk = k;
+                            }
                             z.avail_in = n;
                             z.total_in += p - z.next_in_index;
                             z.next_in_index = p;
-                            write = q;
+                            if (write != q) {
+                                write = q;
+                            }
                             return inflate_flush(r);
                         }
                         n--;
@@ -559,12 +565,18 @@ int proc(int r) {
                     q = write;
                     m = q < read ? read - q - 1 : end - q;
                     if (read != write) {
-                        bitb = b;
-                        bitk = k;
+                        if (bitb != b) {
+                            bitb = b;
+                        }
+                        if (bitk != k) {
+                            bitk = k;
+                        }
                         z.avail_in = n;
                         z.total_in += p - z.next_in_index;
                         z.next_in_index = p;
-                        write = q;
+                        if (write != q) {
+                            write = q;
+                        }
                         return inflate_flush(r);
                     }
                     mode = DONE;

CodenameOne/src/com/codename1/io/gzip/Inflate.java

@@ -641,7 +641,9 @@ int inflateSync() {
         z.total_in += p - z.next_in_index;
         z.next_in_index = p;
         z.avail_in = n;
-        this.marker = m;
+        if (this.marker != m) {
+            this.marker = m;
+        }
 
         // return no joy or set up to restart on a new block
         if (m != 4) {